Document and Entity Information (USD $)	12 Months Ended
Document and Entity Information (USD $)	Sep. 30, 2012	Oct. 27, 2012	Mar. 31, 2012
Document Information [Line Items]
Document Type	10-K
Amendment Flag	false
Document Period End Date	Sep. 30, 2012
Document Fiscal Year Focus	2012
Document Fiscal Period Focus	FY
Trading Symbol	TDG
Entity Registrant Name	TRANSDIGM GROUP INC
Entity Central Index Key	0001260221
Current Fiscal Year End Date	--09-30
Entity Well-known Seasoned Issuer	Yes
Entity Current Reporting Status	Yes
Entity Voluntary Filers	No
Entity Filer Category	Large Accelerated Filer
Entity Common Stock, Shares Outstanding		51,694,655
Entity Public Float			$ 5,540,323,145

CONSOLIDATED BALANCE SHEETS (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
CURRENT ASSETS:
Cash and cash equivalents	$ 440,524	$ 376,183
Trade accounts receivable-Net	235,783	189,293
Inventories-Net	320,503	265,317
Deferred income taxes	29,134	30,844
Prepaid expenses and other	24,587	8,655
Total current assets	1,050,531	870,292
PROPERTY, PLANT AND EQUIPMENT-Net	172,737	150,800
GOODWILL	3,035,502	2,595,747
TRADEMARKS AND TRADE NAMES	467,614	344,942
OTHER INTANGIBLE ASSETS-Net	655,996	483,424
DEBT ISSUE COSTS-Net	62,190	59,007
OTHER	15,047	9,424
TOTAL ASSETS	5,459,617	4,513,636
CURRENT LIABILITIES:
Current portion of long-term debt	20,500	15,500
Accounts payable	74,178	62,110
Accrued liabilities	139,237	129,249
Total current liabilities	233,915	206,859
LONG-TERM DEBT	3,598,625	3,122,875
DEFERRED INCOME TAXES	356,896	310,451
OTHER NON-CURRENT LIABILITIES	51,347	62,502
Total liabilities	4,240,783	3,702,687
STOCKHOLDERS' EQUITY:
Common stock-$.01 par value; authorized 224,400,000 shares; issued 52,157,225 and 50,829,276 at September 30, 2012 and 2011, respectively	521	508
Additional paid-in capital	553,223	464,700
Retained earnings	689,229	364,260
Accumulated other comprehensive loss	(8,051)	(3,277)
Treasury stock, at cost; 505,400 shares at September 30, 2012 and 494,100 shares at September 30, 2011	(16,088)	(15,242)
Total stockholders' equity	1,218,834	810,949
TOTAL LIABILITIES AND STOCKHOLDERS' EQUITY	$ 5,459,617	$ 4,513,636

CONSOLIDATED BALANCE SHEETS (Parenthetical) (USD $)	Sep. 30, 2012	Sep. 30, 2011
Common stock, par value	$ 0.01	$ 0.01
Common stock, shares authorized	224,400,000	224,400,000
Common stock, shares issued	52,157,225	50,829,276
Treasury stock, shares	505,400	494,100

CONSOLIDATED STATEMENTS OF INCOME (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
NET SALES	$ 1,700,208	$ 1,206,021	$ 827,654
COST OF SALES	754,491	544,836	354,588
GROSS PROFIT	945,717	661,185	473,066
SELLING AND ADMINISTRATIVE EXPENSES	201,709	133,711	94,918
AMORTIZATION OF INTANGIBLE ASSETS	44,233	40,339	15,079
INCOME FROM OPERATIONS	699,775	487,135	363,069
INTEREST EXPENSE-Net	211,906	185,256	112,234
Refinancing costs		72,454
INCOME FROM CONTINUING OPERATIONS BEFORE INCOME TAXES	487,869	229,425	250,835
INCOME TAX PROVISION	162,900	77,200	87,390
INCOME FROM CONTINUING OPERATIONS	324,969	152,225	163,445
INCOME FROM DISCONTINUED OPERATIONS, NET OF TAX		19,909
NET INCOME	324,969	172,134	163,445
NET INCOME APPLICABLE TO COMMON STOCK	$ 321,670	$ 169,323	$ 133,132
Net earnings per share-see Note 5:
Net earnings per share from continuing operations-basic and diluted	$ 5.97	$ 2.80	$ 2.52
Net earnings per share from discontinued operations-basic and diluted		$ 0.37
Net earnings per share	$ 5.97	$ 3.17	$ 2.52
Cash dividends paid per common share			$ 7.65
Weighted-average shares outstanding:
Basic and diluted	53,882	53,333	52,923

CONSOLIDATED STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (USD $) In Thousands, except Share data, unless otherwise specified	Total	Common Stock	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income/(Loss)	Treasury Stock
BEGINNING BALANCE at Sep. 30, 2009	$ 819,162	$ 494	$ 388,772	$ 450,647	$ (5,509)	$ (15,242)
BEGINNING BALANCE (in shares) at Sep. 30, 2009		49,448,028				(494,100)
Dividends paid	(404,868)			(404,868)
Unvested dividend equivalent payments	(17,098)			(17,098)
Compensation expense recognized for employee stock options	6,693		6,693
Excess tax benefits related to share- based payment arrangements	17,459		17,459
Exercise of employee stock options (in shares)		477,776
Exercise of employee stock options	6,361	5	6,356
Restricted stock compensation	11		11
Common stock issued (in shares)		2,437
Common stock issued	105		105
Comprehensive income (loss):
Net income	163,445			163,445
Interest rate swaps, net of tax	2,467				2,467
Other comprehensive income (loss)	(758)				(758)
Comprehensive income	165,154
ENDING BALANCE at Sep. 30, 2010	592,979	499	419,396	192,126	(3,800)	(15,242)
ENDING BALANCE (in shares) at Sep. 30, 2010		49,928,241				(494,100)
Compensation expense recognized for employee stock options	12,568		12,568
Excess tax benefits related to share- based payment arrangements	23,411		23,411
Exercise of employee stock options (in shares)		899,395
Exercise of employee stock options	9,208	9	9,199
Restricted stock compensation	6		6
Common stock issued (in shares)		1,640
Common stock issued	120		120
Comprehensive income (loss):
Net income	172,134			172,134
Interest rate swaps, net of tax	(1,077)				(1,077)
Foreign currency translation adjustments	1,498				1,498
Other comprehensive income (loss)	102				102
Comprehensive income	172,657
ENDING BALANCE at Sep. 30, 2011	810,949	508	464,700	364,260	(3,277)	(15,242)
ENDING BALANCE (in shares) at Sep. 30, 2011		50,829,276				(494,100)
Compensation expense recognized for employee stock options	22,151		22,151
Excess tax benefits related to share- based payment arrangements	50,555		50,555
Exercise of employee stock options (in shares)		1,327,029
Exercise of employee stock options	15,710	13	15,697
Treasury stock purchased, shares	(11,300)					(11,300)
Treasury stock purchased	(846)					(846)
Common stock issued (in shares)		920
Common stock issued	120		120
Comprehensive income (loss):
Net income	324,969			324,969
Interest rate swaps, net of tax	(2,635)				(2,635)
Foreign currency translation adjustments	(1,315)				(1,315)
Other comprehensive income (loss)	(824)				(824)
Comprehensive income	320,195
ENDING BALANCE at Sep. 30, 2012	$ 1,218,834	$ 521	$ 553,223	$ 689,229	$ (8,051)	$ (16,088)
ENDING BALANCE (in shares) at Sep. 30, 2012		52,157,225				(505,400)

CONSOLIDATED STATEMENTS OF CASH FLOWS (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
OPERATING ACTIVITIES:
Net income	$ 324,969	$ 172,134	$ 163,445
Net income from discontinued operations		(19,909)
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	23,692	20,092	15,086
Amortization of intangible assets	44,535	40,368	15,079
Amortization of debt issue costs	12,544	9,842	7,578
Refinancing costs		72,454
Non-cash equity compensation	22,151	12,574	6,704
Excess tax benefits related to share-based payment arrangements	(50,555)	(23,411)	(17,459)
Deferred income taxes	24,800	8,888	1,900
Changes in assets/liabilities, net of effects from acquisitions of businesses:
Trade accounts receivable	(1,957)	(14,993)	(17,721)
Inventories	(416)	(9,661)	2,893
Income taxes receivable/payable	34,097	(22,259)	13,094
Other assets	(10,564)	(2,692)	513
Accounts payable	(3,620)	4,484	4,933
Accrued and other liabilities	(5,791)	12,475	1,259
Net cash provided by operating activities	413,885	260,386	197,304
INVESTING ACTIVITIES:
Capital expenditures	(25,246)	(18,026)	(12,887)
Acquisition of businesses, net of cash acquired	(868,696)	(1,650,363)	(166,557)
Cash proceeds from sales of discontinued operations		271,361
Cash proceeds from sale of business	17,650
Cash proceeds from sale of real estate			2,885
Net cash used in investing activities	(876,292)	(1,397,028)	(176,559)
FINANCING ACTIVITIES:
Excess tax benefits related to share-based payment arrangements	50,555	23,411	17,459
Proceeds from exercise of stock options	15,710	9,208	6,361
Dividends paid	(3,299)	(2,811)	(404,868)
Treasury stock purchased	(846)
Proceeds from new senior secured credit facility-net	484,316	1,500,048
Repayment on new senior secured credit facility	(19,250)	(11,625)
Proceeds from senior subordinated notes		1,582,184	404,248
Repurchase of senior subordinated notes due 2014		(1,041,894)
Repayment of existing senior secured credit facility		(780,000)
Net cash provided by financing activities	527,186	1,278,521	23,200
EFFECT OF EXCHANGE RATE CHANGES ON CASH AND CASH EQUIVALENTS	(438)	192
NET INCREASE IN CASH AND CASH EQUIVALENTS	64,341	142,071	43,945
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	376,183	234,112	190,167
CASH AND CASH EQUIVALENTS, END OF PERIOD	440,524	376,183	234,112
SUPPLEMENTAL DISCLOSURE OF CASH FLOW INFORMATION:
Cash paid during the period for interest	197,787	155,849	97,713
Cash paid during the period for income taxes	103,938	88,367	72,498
7 3/4% Senior Subordinated Notes, Due 2018
FINANCING ACTIVITIES:
Proceeds from senior subordinated notes		1,582,184
7 3/4% Senior Subordinated Notes, Due 2014
FINANCING ACTIVITIES:
Proceeds from senior subordinated notes			$ 404,248

DESCRIPTION OF THE BUSINESS

12 Months Ended

Sep. 30, 2012

DESCRIPTION OF THE BUSINESS

1.	DESCRIPTION OF THE BUSINESS

Description of the Business—TransDigm Group Incorporated (“TD Group”), through its wholly-owned subsidiary, TransDigm Inc., is a leading global designer, producer and supplier of highly engineered aircraft components for use on nearly all commercial and military aircraft in service today. TransDigm Inc. along with TransDigm Inc.’s direct and indirect wholly-owned operating subsidiaries (collectively, with TD Group, the “Company” or “TransDigm”), offers a broad range of proprietary aerospace components. TD Group has no significant assets or operations other than its 100% ownership of TransDigm Inc. TD Group’s common stock is listed on The New York Stock Exchange, or the NYSE, under the trading symbol “TDG.”

Major product offerings, substantially all of which are ultimately provided to end-users in the aerospace industry, include mechanical/electro-mechanical actuators and controls, ignition systems and engine technology, specialized pumps and valves, power conditioning devices, specialized AC/DC electric motors and generators, NiCad batteries and chargers, engineered latching and locking devices, rods and locking devices, engineered connectors and elastomers, cockpit security components and systems, specialized cockpit displays, aircraft audio systems, specialized lavatory components, seatbelts and safety restraints, engineered interior surfaces and lighting and control technology.

Separate Financial Statements—Separate financial statements of TransDigm Inc. are not presented because TransDigm Inc.’s 7³/₄% senior subordinated notes are fully and unconditionally guaranteed on a senior subordinated basis by TD Group and all existing 100% owned domestic subsidiaries of TransDigm Inc. and because TD Group has no significant operations or assets separate from its investment in TransDigm Inc.

Reclassifications—Certain reclassifications of prior year amounts have been made to the Consolidated Statement of Cash Flows to conform to current year classification to reflect the effect of exchange rate changes on cash and cash equivalents relating to our foreign operations.

ACQUISITIONS

12 Months Ended

Sep. 30, 2012

ACQUISITIONS

2.	ACQUISITIONS

Aero-Instruments Co., LLC—On September 17, 2012, TransDigm Inc. acquired all of the outstanding equity interests in Aero-Instruments Co., LLC (“Aero-Instruments”), for approximately $34.7 million in cash, subject to adjustments based on the level of working capital as of the closing date of the acquisition. Aero-Instruments designs and manufactures highly engineered air data sensors including pitot probes, pitot-static probes, static pressure ports, angle of attack, temperature sensors and flight test equipment for use primarily in the business jet and helicopter markets. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $15 million of goodwill recognized for the acquisition will be deductible for tax purposes.

AmSafe Global Holdings, Inc.—On February 15, 2012, TransDigm Inc. acquired all of the outstanding stock of AmSafe Global Holdings, Inc. (“AmSafe”), for approximately $749.7 million in cash, which includes a purchase price adjustment of $0.5 million paid in the third quarter of fiscal 2012. AmSafe is a leading supplier of innovative, highly engineered and proprietary safety and restraint equipment used primarily in the global aerospace industry. These products fit well with TransDigm’s overall business direction. The distribution business acquired as part of AmSafe was sold on August 16, 2012 for approximately $17.7 million in cash, subject to adjustments based on the level of working capital as of the closing date of the sale.The Company financed the acquisition through a combination of new senior bank debt of $500 million and cash. See Note 11 to the Consolidated Financial Statements.

The total purchase price was allocated to the underlying assets acquired and liabilities assumed based upon management’s estimated fair values at the date of acquisition. To the extent the purchase price exceeded the estimated fair value of the net identifiable tangible and intangible assets acquired, such excess was allocated to goodwill. The following table summarizes the purchase price allocation of the estimated fair values of the assets acquired and liabilities assumed at the transaction date (in thousands).


Assets acquired:
Current assets, excluding cash acquired	$	127,600
Property, plant and equipment		20,794
Intangible assets		270,500
Goodwill		403,025
Other		4,239

Total assets acquired	$	826,158

Liabilities assumed:
Current liabilities	$	24,152
Deferred income taxes—long term		49,343
Other noncurrent liabilities		2,932

Total liabilities assumed	$	76,427

Net assets acquired	$	749,731

The Company expects that of the $403 million of goodwill recognized for the acquisition approximately $77 million will be deductible for tax purposes.

Harco Laboratories, Incorporated—On December 9, 2011, TransDigm Inc. acquired all of the outstanding stock of Harco Laboratories, Incorporated (“Harco”), for approximately $83.3 million in cash, which includes a purchase price adjustment of $0.4 million paid in the second quarter of fiscal 2012. Harco designs and manufactures highly engineered thermocouples, sensors, engine cable assemblies and related products for commercial aircraft. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $56 million of goodwill recognized for the acquisition will not be deductible for tax purposes.

Schneller Holdings—On August 31, 2011, TransDigm Inc. acquired all of the outstanding equity interests in Schneller Holdings LLC (“Schneller”) for approximately $288.6 million in cash, which includes a purchase price adjustment of $1.0 million paid in the first quarter of fiscal 2012. Schneller designs and manufactures proprietary, highly engineered laminates, thermoplastics, and non-textile flooring for use primarily on side walls, lavatories, galleys, bulkheads and cabin floors for commercial aircraft. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $168 million of goodwill recognized for the acquisition will be deductible for tax purposes.

Talley Actuation—On December 31, 2010, AeroControlex Group, Inc., a wholly owned subsidiary of TransDigm Inc., acquired the actuation business of Telair International Inc. (“Talley Actuation”), a wholly-owned subsidiary of Teleflex Incorporated, for approximately $93.6 million in cash, which includes a purchase price adjustment of $0.3 million received in the third quarter of fiscal 2011. Talley Actuation manufactures proprietary, highly engineered electro-mechanical products and other components for commercial and military aircraft. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $70 million of goodwill recognized for the acquisition will be deductible for tax purposes.

McKechnie Aerospace Holdings, Inc.—On December 6, 2010, TransDigm Inc. acquired all of the outstanding stock of McKechnie Aerospace Holdings Inc. (“McKechnie Aerospace”), for approximately $1.27 billion in cash, which includes a purchase price adjustment of $0.3 million paid in the third quarter of fiscal 2011. McKechnie Aerospace, through its subsidiaries, is a leading global designer, producer and supplier of aerospace components, assemblies and subsystems for commercial aircraft, regional/business jets, military fixed wing and rotorcraft. Some of the businesses acquired as part of McKechnie Aerospace have been divested. See Note 21 to the Consolidated Financial Statements. The remaining products fit well with TransDigm’s overall business direction.

The Company financed the McKechnie Aerospace acquisition, repaid borrowings under the previous senior secured credit facility and redeemed outstanding 7³/₄% Senior Subordinated Notes due 2014 through a combination of the offering of $1.60 billion of 7³/₄% Senior Subordinated Notes due 2018 and new term loan borrowings of $1.55 billion due 2017. See Note 11 to the Consolidated Financial Statements.

The following table summarizes the purchase price allocation of the estimated fair values of the assets acquired and liabilities assumed at the transaction date (in thousands).


Assets acquired:
Current assets, excluding cash acquired	$	109,289
Property, plant and equipment		48,901
Intangible assets		433,000
Goodwill		864,934

Total assets acquired	$	1,456,124

Liabilities assumed:
Current liabilities	$	40,004
Deferred income taxes—long term		118,591
Other noncurrent liabilities		31,837

Total liabilities assumed	$	190,432

Net assets acquired	$	1,265,692

The Company expects that the approximately $865 million of goodwill recognized for the acquisition will not be deductible for tax purposes.

The results of operations of McKechnie Aerospace are included in the Company’s consolidated financial statements from the date of the transaction. The Company recorded net sales of $212.2 million from the date of acquisition through September 30, 2011. It is impracticable to determine a meaningful measure of the earnings of the acquired business from the date of acquisition through September 30, 2011 because certain McKechnie Aerospace plant facilities have been integrated into other TransDigm operations. Had the McKechnie acquisition and related financing transactions occurred at the beginning of the fiscal year ended September 30, 2010, unaudited pro forma consolidated results for the year ended September 30, 2011 would have been as follows (in thousands, except per share data):


	Fiscal Years Ended September 30,
	2011		2010
Net sales	$	1,247,386	$	1,033,059

Net income applicable to common stock from continuing operations	$	217,575	$	44,614

Net earnings per share from continuing operations:
Basic and diluted	$	4.08	$	0.84

The unaudited pro forma consolidated results are based on the Company’s historical financial statements and those of McKechnie Aerospace and do not necessarily indicate the results of operations that would have resulted had the acquisition actually been completed at the beginning of the applicable period presented. The pro forma financial information assumes that the companies were combined as of October 1, 2009. The pro forma results for the fiscal year ended September 30, 2010 reflect the business combination accounting effects from the acquisition including amortization charges from the acquired intangible assets, inventory purchase accounting adjustments charged to cost of sales as the inventory is sold, increase in interest expense associated with debt incurred to fund the acquisition, refinancing costs associated with the refinancing of the Company’s entire debt structure and acquisition-related transaction costs. The unaudited pro forma consolidated results do not give effect to the synergies of the acquisition and are not indicative of the results of operations in future periods.

Semco Instruments—On September 3, 2010, TransDigm Inc. completed the acquisition of Semco Instruments, Inc. (“Semco Instruments”) for approximately $73.6 million in cash, which includes a purchase price adjustment of $3.0 million paid in the first quarter of fiscal 2011. Semco Instruments manufactures proprietary, highly engineered components for major turbo-prop, turbo-fan, and turbo-shaft engines, which are primarily used on helicopters, business jets and selected regional airplanes. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $41 million of goodwill recognized for the acquisition will not be deductible for tax purposes.

Dukes Aerospace—On December 2, 2009, Dukes Aerospace, Inc., a newly formed, wholly owned subsidiary of TransDigm Inc., acquired substantially all of the aerospace related assets and certain liabilities from Dukes, Inc. and GST Industries, Inc. (collectively “Dukes Aerospace”) for approximately $95.5 million in cash, which includes a purchase price adjustment of $0.2 million received in the third quarter of fiscal 2011. In addition, the agreement provides for potential earn-out payments up to a total of $60 million over four years based on the achievement of certain growth targets. The initial purchase price allocation included a fair value liability of $8.0 million recorded for the potential earn-out payments. During the third quarter of fiscal 2011, the Company reversed $3.0 million of the earn-out liability based on lower growth projections relative to the required growth targets for the last three years of the four-year earn-out arrangement. During the fourth quarter of fiscal 2012, the Company reversed the remaining $5.0 million of the earn-out liability based on the lower growth projections relative to the required growth targets. The reversal of earn-out liability is included in selling and administrative expenses in the consolidated statements of income for the fiscal year ended September 30, 2011. The Dukes Aerospace business supplies proprietary, highly engineered components primarily to the business jet, regional jet, and military aerospace markets, along with commercial and military helicopter markets. The products are comprised primarily of highly engineered valves and certain pumps, solenoids and related components. These products fit well with TransDigm’s overall business direction. The Company expects that the approximately $64 million of goodwill recognized for the acquisition will be deductible for tax purposes.

The Company accounted for the acquisitions of Aero-Instruments, AmSafe, Harco, McKechnie Aerospace, Schneller, Talley Actuation, Semco Instruments and Dukes Aerospace, (collectively, the “Acquisitions”) using the acquisition method and included the results of operations of the Acquisitions in its consolidated financial statements from the effective date of each acquisition. The Company is in the process of obtaining a third-party valuation of certain tangible and intangible assets of Aero-Instruments, AmSafe and Harco, therefore, the values attributed to those acquired assets in the consolidated financial statements are subject to adjustment. Pro forma net sales and results of operations for the acquisitions of Aero-Instruments, AmSafe, Harco, Schneller, Talley Actuation, Semco Instruments and Dukes Aerospace had they occurred at the beginning of the applicable fiscal year ended September 30, 2012 or 2011, are not significant and, accordingly, are not provided.

The Acquisitions strengthen and expand the Company’s position to design, produce and supply highly-engineered proprietary aerospace components in niche markets with significant aftermarket content and provide opportunities to create value through the application of our three core value-driven operating strategies (obtaining profitable new business, improving our cost structure, and providing highly engineered value-added products to customers). The purchase price paid for each acquisition reflects the current earnings before interest, taxes, depreciation and amortization (EBITDA) and cash flows, as well as, the future EBITDA and cash flows expected to be generated by the business, which are driven in most cases by the recurring aftermarket consumption over the life of a particular aircraft, estimated to be approximately 30 years.

SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	12 Months Ended
SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES (Policies)	Sep. 30, 2012
Basis of Presentation and Consolidation	*Basis of Presentation and Consolidation*—The accompanying consolidated financial statements were prepared in conformity with generally accepted accounting principles in the United States (“GAAP”) and include the accounts of TD Group and subsidiaries. All significant intercompany balances and transactions have been eliminated.
Revenue Recognition and Related Allowances	*Revenue Recognition and Related Allowances*—Revenue is recognized from the sale of products when title and risk of loss passes to the customer, which is generally at the time of shipment. Substantially all sales are made pursuant to firm, fixed-price purchase orders received from customers. Provisions for estimated returns, uncollectible accounts and the cost of repairs under contract warranty provisions are provided for in the same period as the related revenues are recorded and are principally based on historical results modified, as appropriate, by the most current information available. Due to uncertainties in the estimation process, it is possible that actual results may vary from the estimates.
Shipping and Handling Costs	*Shipping and Handling Costs*—Shipping and handling costs are included in cost of sales in the Consolidated Statements of Income.
Research and Development Costs	*Research and Development Costs*—The Company expenses research and development costs as incurred and classifies such amounts in selling and administrative expenses. The expense recognized for research and development costs for the years ended September 30, 2012, 2011 and 2010 was approximately $27.9 million, $19.3 million, and $13.9 million, respectively.
Cash Equivalents	*Cash Equivalents*—The Company considers all highly liquid investments with a maturity of three months or less when purchased to be cash equivalents.
Allowance for Uncollectible Accounts	*Allowance for Uncollectible Accounts*—The Company reserves for amounts determined to be uncollectible based on specific identification of losses and estimated losses based on historical experience. The allowance also incorporates a provision for the estimated impact of disputes with customers. The determination of the amount of the allowance for doubtful accounts is subject to significant levels of judgment and estimation by management. If circumstances change or economic conditions deteriorate or improve, the allowance for doubtful accounts could increase or decrease.
Inventories	*Inventories*—Inventories are stated at the lower of cost or market. Cost of inventories is determined by the average cost and the first-in, first-out (FIFO) methods for all locations except CEF Industries, Inc. which determines the cost of inventories using the last-in, first-out (LIFO) method. Approximately 6% of the inventory was valued under the LIFO method at September 30, 2012. Provision for potentially obsolete or slow-moving inventory is made based on management’s analysis of inventory levels and future sales forecasts. In accordance with industry practice, all inventories are classified as current assets even though a portion of the inventories may not be sold within one year.
Property, Plant and Equipment	*Property, Plant and Equipment*—Property, plant and equipment are stated at cost. Depreciation is computed using the straight-line method over the following estimated useful lives: land improvements from 10 to 20 years, buildings and improvements from 5 to 30 years, machinery and equipment from 2 to 10 years and furniture and fixtures from 3 to 10 years. Property, plant and equipment is assessed for potential impairment whenever indicators of impairment are present by determining whether the carrying value of the property can be recovered through projected, undiscounted cash flows from future operations over the property’s remaining estimated useful life. Any impairment recognized is the amount by which the carrying amount exceeds the fair value of the asset.
Debt Issue Costs, Premiums and Discounts	*Debt Issue Costs, Premiums and Discounts*—The cost of obtaining financing as well as premiums and discounts are amortized using the effective interest method over the terms of the respective obligations/securities.
Intangible Assets	*Intangible Assets*—Intangible assets consist of identifiable intangibles acquired or recognized in accounting for the acquisitions (trademarks, trade names, technology, order backlog and a license agreement) and goodwill. Goodwill and intangible assets that have indefinite useful lives (trademarks and trade names) are subject to annual impairment testing. Management determines fair value using a discounted future cash flow analysis or other accepted valuation techniques. The Company performs an annual impairment test for goodwill and other intangible assets as of the first day of the fourth fiscal quarter of each year, or more frequently, if an event occurs or circumstances change that would more likely than not reduce fair value below current value. A two-step impairment test is used to identify potential goodwill impairment. The first step of the goodwill impairment test, used to identify potential impairment, compares the fair value of a reporting unit (as defined) with its carrying amount, including goodwill. If the fair value of the reporting unit exceeds its carrying amount, goodwill is not considered impaired, and the second step of the goodwill impairment test is unnecessary. The second step measures the amount of impairment, if any, by comparing the carrying value of the goodwill associated with a reporting unit to the implied fair value of the goodwill derived from the estimated overall fair value of the reporting unit and the individual fair values of the other assets and liabilities of the reporting unit. GAAP requires that the annual, and any interim, impairment assessment be performed at the reporting unit level. The reporting unit level is the operating subsidiary level for the Company. Substantially all goodwill was determined and recognized for each operating subsidiary pursuant to the accounting for the merger or acquisition as of the date of each transaction, and therefore the allocation of goodwill among reporting units was immaterial for purposes of the impairment assessment. With respect to acquisitions integrated into an existing operating subsidiary, any related goodwill is combined with goodwill of the operating subsidiary. The impairment test for indefinite lived intangible assets consists of a comparison between their fair values and carrying values. If the carrying amounts of intangible assets that have indefinite useful lives exceed their fair values, an impairment loss will be recognized in an amount equal to the sum of any such excesses. The Company assesses the recoverability of its amortizable intangible assets only when indicators of impairment are present by determining whether the amortization over their remaining lives can be recovered through projected, undiscounted cash flows from future operations. Amortization of amortizable intangible assets is computed using the straight-line method over the following estimated useful lives: technology from 20 to 22 years, order backlog over one year, and a license agreement over 20 years.
Stock Option Plans	*Stock Option Plans*—The Company records stock-based compensation measured using the fair value method of accounting. Compensation expense is recorded over the vesting periods of the options.
Income Taxes	*Income Taxes*—The Company accounts for income taxes using an asset and liability approach. Deferred taxes are recorded for the difference between the book and tax basis of various assets and liabilities. A valuation allowance is provided when it is more likely than not that some or all of a deferred tax asset will not be realized.
Contingencies	*Contingencies*—During the ordinary course of business, the Company is from time to time threatened with, or may become a party to, legal actions and other proceedings. While the Company is currently involved in certain legal proceedings, it believes the results of these proceedings will not have a material adverse effect on its financial condition, results of operations, or cash flows. The Company believes that its potential exposure to such legal actions is adequately covered by its aviation product and general liability insurance.
Estimates	*Estimates*—The preparation of financial statements in conformity with U.S. generally accepted accounting principles requires management to make estimates and assumptions that affect the reported amounts of assets and liabilities and disclosure of contingent assets and liabilities at the date of the financial statements and the reported amounts of revenues and expenses during the reporting period. Actual results could differ from those estimates.
Comprehensive Income (Loss)	*Comprehensive Income (Loss)*—The term “comprehensive income (loss)” represents the change in stockholders’ equity from transactions and other events and circumstances resulting from non-stockholder sources. The Company’s accumulated other comprehensive income or loss, consisting principally of fair value adjustments to its interest rate swap agreements (net of tax), cumulative foreign currency translation adjustments and pension liability adjustments (net of tax), is reported separately in the accompanying consolidated statements of changes in stockholders’ equity. See Note 20 to the Consolidated Financial Statements.
Segment Reporting	*Segment Reporting*—Management evaluates the Company as one reporting segment in the aerospace industry. The Company is engaged in the design, manufacture and sale of highly engineered aircraft components used in aerospace and defense applications through its wholly-owned subsidiaries. Substantially all of the Company’s operations are located within the United States.
Earnings per Share	*Earnings per Share*—Earnings per share information is determined using the two-class method, which includes the weighted-average number of common shares outstanding during the period and other securities that participate in dividends (“participating securities”). Our vested stock options are considered “participating securities” because they include non-forfeitable rights to dividends. In applying the two-class method, earnings are allocated to both common stock shares and participating securities based on their respective weighted-average shares outstanding for the period. Diluted earnings per share information may include the additional effect of other securities, if dilutive, in which case the dilutive effect of such securities is calculated using the treasury stock method.

Description of Business - Additional Information (Detail)	12 Months Ended
	Sep. 30, 2012
Nature Of Business [Line Items]
Percentage of ownership in subsidiary	100.00%
Interest rate of senior subordinated debt	7.75%

Acquisitions - Additional Information (Detail) (USD $)	1 Months Ended	12 Months Ended					12 Months Ended			1 Months Ended		1 Months Ended	12 Months Ended											1 Months Ended
Acquisitions - Additional Information (Detail) (USD $)	Oct. 31, 2009	Sep. 30, 2012 Y	Sep. 30, 2011	Sep. 30, 2010	Sep. 30, 2012 7 3/4% Senior Subordinated Notes, Due 2018	Sep. 30, 2011 7 3/4% Senior Subordinated Notes, Due 2018	Sep. 30, 2011 McKechnie Aerospace Holdings, Inc.	Jun. 30, 2011 McKechnie Aerospace Holdings, Inc.	Dec. 06, 2010 McKechnie Aerospace Holdings, Inc.	Dec. 31, 2010 McKechnie Aerospace Holdings, Inc. 7 3/4% Senior Subordinated Notes, Due 2018	Dec. 31, 2010 McKechnie Aerospace Holdings, Inc. 7 3/4% Senior Subordinated Notes, Due 2014	Dec. 31, 2010 McKechnie Aerospace Holdings, Inc. Senior Subordinated Notes Due 2017	Sep. 30, 2012 AmSafe Global Holdings, Inc.	Jun. 30, 2012 AmSafe Global Holdings, Inc.	Feb. 15, 2012 AmSafe Global Holdings, Inc.	Mar. 31, 2012 Harco Laboratories, Incorporated	Dec. 09, 2011 Harco Laboratories, Incorporated	Dec. 31, 2011 Schneller Holdings LLC	Aug. 31, 2011 Schneller Holdings LLC	Jun. 30, 2011 Talley Actuation	Dec. 31, 2010 Talley Actuation	Dec. 31, 2011 Semco Instruments	Sep. 03, 2010 Semco Instruments	Dec. 02, 2009 Dukes Aerospace Y	Sep. 30, 2012 Dukes Aerospace	Jun. 30, 2011 Dukes Aerospace	Sep. 17, 2012 Aero-Instruments Co., LLC
Business Acquisition [Line Items]
Cash consideration paid to acquire business									$ 1,270,000,000						$ 749,700,000		$ 83,300,000		$ 288,600,000		$ 93,600,000		$ 73,600,000	$ 95,500,000			$ 34,700,000
Amount of goodwill expected to be tax deductible															77,000,000				168,000,000		70,000,000			64,000,000			15,000,000
Business acquisition, purchase price adjustment paid								300,000						500,000		400,000		1,000,000		300,000		3,000,000				200,000
Cash proceeds from sale of business		17,650,000
Cost of business acquisition financed new senior bank debt													500,000,000
Goodwill									864,934,000						403,025,000		56,000,000						41,000,000
Proceeds from senior subordinated notes			1,582,184,000	404,248,000						1,600,000,000
Debt instrument, maturity date		2018			2018	2018				2018	2014	2017
Debt instrument, stated percentage										7.75%	7.75%
Term loan borrowings	404,500,000	484,316,000	1,500,048,000									1,550,000,000
NET SALES		1,700,208,000	1,206,021,000	827,654,000			212,200,000
Total potential earn-out payments																								60,000,000
Potential earn-out period, in years																								4
Fair value liability for potential earn-out payments																								8,000,000
Potential earn-out payments reversed																									$ 5,000,000	$ 3,000,000
Estimated useful life of aircraft (in years)		30

Purchase Price Allocation Estimated Fair Values of Assets Acquired Liabilities Assumed (Detail) (USD $) In Thousands, unless otherwise specified	Feb. 15, 2012 AmSafe Global Holdings, Inc.	Dec. 06, 2010 McKechnie Aerospace Holdings, Inc.
Schedule of Business Acquisitions, Purchase Price Allocation [Line Items]
Current assets, excluding cash acquired	$ 127,600	$ 109,289
Property, plant and equipment	20,794	48,901
Intangible assets	270,500	433,000
Goodwill	403,025	864,934
Other	4,239
Total assets acquired	826,158	1,456,124
Current liabilities	24,152	40,004
Deferred income taxes-long term	49,343	118,591
Other noncurrent liabilities	2,932	31,837
Total liabilities assumed	76,427	190,432
Net assets acquired	$ 749,731	$ 1,265,692

Unaudited Pro Forma Consolidated Results (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	12 Months Ended
	Sep. 30, 2011	Sep. 30, 2010
Business Acquisition, Pro Forma Information [Line Items]
Net sales	$ 1,247,386	$ 1,033,059
Net income applicable to common stock from continuing operations	$ 217,575	$ 44,614
Net earnings per share from continuing operations:
Basic and diluted	$ 4.08	$ 0.84

Trade Accounts Receivable (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Trade Accounts Receivable Securitization and Sale Program [Line Items]
Trade accounts receivable-gross	$ 240,743	$ 192,166
Allowance for uncollectible accounts	(4,960)	(2,873)
Trade accounts receivable-net	$ 235,783	$ 189,293

Inventories (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Schedule of Inventory [Line Items]
Raw materials and purchased component parts	$ 203,809	$ 160,402
Work-in-progress	102,645	85,612
Finished Goods	48,395	43,192
Total	354,849	289,206
Reserves for excess and obsolete inventory and LIFO	(34,346)	(23,889)
Inventories-net	$ 320,503	$ 265,317

Property, Plant and Equipment (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Property, Plant, and Equipment Disclosure [Line Items]
Land and improvements	$ 39,685	$ 40,912
Buildings and improvements	78,631	58,692
Machinery, equipment and other	167,435	137,124
Construction in progress	10,171	8,250
Total	295,922	244,978
Accumulated depreciation	(123,185)	(94,178)
Property, plant and equipment-net	$ 172,737	$ 150,800

Intangible Assets Subjects to Amortization (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 772,484	$ 582,498
Accumulated Amortization	116,488	99,074
Net	655,996	483,424
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	723,231	546,726
Accumulated Amortization	105,995	75,426
Net	617,236	471,300
Order backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	5,910	24,799
Accumulated Amortization	3,965	17,895
Net	1,945	6,904
Other intangible assets
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	43,343	10,973
Accumulated Amortization	6,528	5,753
Net	$ 36,815	$ 5,220

Intangible Assets Acquired (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	$ 595,405
Intangible assets subject to amortization	186,460
Total - Intangible assets both subject to and not subject to amortization	781,865
Amortization Period (in years)	19 years 3 months 18 days
Goodwill
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	473,895
Trademarks and trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets not subject to amortization	121,510
Technology
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization	175,750
Amortization Period (in years)	20 years
Order backlog
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization	5,910
Amortization Period (in years)	1 year
Other intangible assets
Acquired Finite-Lived Intangible Assets [Line Items]
Intangible assets subject to amortization	$ 4,800
Amortization Period (in years)	15 years

Summary of Changes in Carrying Value of Goodwill (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 2,595,747	$ 1,571,664
Goodwill acquired during the year (Note 2)	473,895	1,129,145
Divestitures (Note 21)		(103,880)
Purchase price allocation adjustments	(26,109)
Other	(8,031)	(1,182)
Goodwill, Ending Balance	$ 3,035,502	$ 2,595,747

Accrued Liabilities (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Schedule of Accrued Liabilities [Line Items]
Compensation and related benefits	$ 39,446	$ 24,824
Interest	39,003	37,065
Interest rate swap agreements	9,800
Product warranties	8,604	8,722
Income taxes payable		8,937
Other	42,384	49,701
Total	$ 139,237	$ 129,249

Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Debt Instrument [Line Items]
Total debt outstanding	$ 3,619,125	$ 3,138,375
Less current portion	20,500	15,500
LONG-TERM DEBT	3,598,625	3,122,875
Term Loans
Debt Instrument [Line Items]
Debt instrument, outstanding	2,019,125	1,538,375
7 3/4% Senior Subordinated Notes, Due 2018
Debt Instrument [Line Items]
Debt instrument, outstanding	$ 1,600,000	$ 1,600,000

Debt - Additional Information (Detail) (USD $)	1 Months Ended	3 Months Ended			12 Months Ended			1 Months Ended	12 Months Ended		1 Months Ended		12 Months Ended		1 Months Ended	12 Months Ended	1 Months Ended			1 Months Ended	12 Months Ended
Debt - Additional Information (Detail) (USD $)	Oct. 31, 2009	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010	Dec. 31, 2010 Existing Senior Secured Credit Facility	Sep. 30, 2012 Existing Senior Secured Credit Facility	Sep. 30, 2012 7 3/4% Senior Subordinated Notes due 2018	Feb. 15, 2012 New Senior Secured Credit Facility	Feb. 14, 2011 New Senior Secured Credit Facility	Sep. 30, 2012 New Senior Secured Credit Facility D	Jun. 27, 2011 New Senior Secured Credit Facility Derivative	Feb. 15, 2012 Assumption Agreement	Sep. 30, 2012 TransDigm's Foreign Subsidiaries	Dec. 31, 2010 7 3/4% Senior Subordinated Notes, Due 2018	Sep. 30, 2012 7 3/4% Senior Subordinated Notes, Due 2018	Sep. 30, 2011 7 3/4% Senior Subordinated Notes, Due 2018	Oct. 31, 2009 7 3/4% Senior Subordinated Notes, Due 2014	Sep. 30, 2011 7 3/4% Senior Subordinated Notes, Due 2014
Debt Instrument [Line Items]
Net proceeds from debt after issuance fees and expenses	$ 404,500,000				$ 484,316,000	$ 1,500,048,000		$ 1,550,000,000				$ 1,550,000,000
Revolving credit facility amount								245,000,000							310,000,000
Debt instrument, maturity date					2018					2018								2018	2018
Debt instrument, stated percentage										7.75%
Additional loan amount											500,000,000				65,000,000
Date the credit facility was fully drawn											February 15, 2012
Letters of credit outstanding					7,100,000
Borrowings available under credit facility									302,900,000
Maturity date of credit facility									2015-12				2017-02
Quarterly principal payments													5,100,000
Applicable interest rate on term loan													4.00%
Floor basis spread on LIBO													1.00%
Interest rate swap, notional amount													353,000,000	353,000,000
Number of forward stating interest rate swap agreement														3
Fixed rate of interest under interest rate swap													5.17%	5.17%
Percentage of voting capital stock																65.00%
Term loan mandatory principal prepayment commencement period from fiscal year (days)													90
Percentage of principal amount of term loan to be prepaid													100.00%
Debt instrument, face amount						3,619,125,000											1,600,000,000
Percentage of principal amount of debt on issue price																	100.00%
Debt instrument, redemption rate					103.875%
Debt instrument redemption rate in addition to accrued and unpaid interest					100.00%
Redemption rate of debt instrument in addition to accrued and unpaid interest out of proceed from equity offering					107.75%
Redemption rate of debt instrument demanded by holder under change in business control					101.00%
Refinancing costs						72,454,000
Premium paid to redeem notes																					41,900,000
Write-off of debt issue costs and unamortized premium and discount																					25,700,000
Settlement of interest rate swap agreement and other expenses																					4,900,000
Special cash dividend paid per share	$ 7.65						$ 7.65
Proceeds from issuance of debt																				425,000,000
Special cash dividend and dividend equivalents paid	$ 36,400,000	$ 3,300,000	$ 2,800,000	$ 404,900,000

Future Maturities of Long-Term Debt (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2011
Long Term Debt Maturities Repayments Of Principal [Line Items]
Year ended September 30, 2013	$ 20,500
Year ended September 30, 2014	20,500
Year ended September 30, 2015	20,500
Year ended September 30, 2016	20,500
Year ended September 30, 2017	1,937,125
Thereafter	1,600,000
Total	$ 3,619,125

Retirement Plans - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012 CompensationPlan	Sep. 30, 2011	Sep. 30, 2010
Defined Benefit Plan Disclosure [Line Items]
Defined contribution plan, cost recognized	$ 4.9	$ 3.5	$ 2.6
Number of non-contributory defined benefit pension plans	4
Non-contributory defined benefit pension plans, qualified	The Company has three qualified, non-contributory defined benefit pension plans, which together cover certain union employees. One plan covers certain employees of a business acquired during the year ended September 30, 2012.
Defined benefit plan, assets	60.1	6.7
Defined benefit plan, accumulated benefit obligation	62.9	9.7
Net period pension, cost recognized	0.6	0.4	0.3
Qualified Pension Plans
Defined Benefit Plan Disclosure [Line Items]
Number of non-contributory defined benefit pension plans	3
Defined benefit pension plan, liabilities	4.7	3.0
Non-qualified
Defined Benefit Plan Disclosure [Line Items]
Defined benefit pension plan, liabilities	9.5	8.8
Defined benefit plan, net periodic pension cost	0.4
Non-qualified \| Maximum
Defined Benefit Plan Disclosure [Line Items]
Defined benefit plan, net periodic pension cost		$ 0.1

Components of Deferred Taxes (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Schedule of Deferred Income Tax Assets and Liabilities [Line Items]
Employee benefits, compensation and other accrued obligations	$ 31,711	$ 16,059
Net operating losses	14,637	16,500
Inventory	12,330	10,715
Tax credits	9,347
Environmental	6,975	7,412
Interest rate swaps	3,652	2,087
Product warranties	3,560	3,534
Other accrued liabilities		4,692
Total	82,212	60,999
Less: Valuation allowance	(16,150)	(15,874)
Total deferred tax assets	66,062	45,125
Intangible assets	361,226	302,273
Property, plant and equipment	23,119	22,459
Unremitted foreign earnings	3,714
Other	5,765
Total deferred tax liabilities	393,824	324,732
Total net deferred tax liabilities	$ 327,762	$ 279,607

Income Taxes - Additional Information (Detail) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Income Tax Contingency [Line Items]
Net tax loss carryforwards, expiration years	2013 to 2031
Deferred tax asset foreign tax credit carryforward	$ 7.0
Foreign tax credit carryforwards expiration, years	2018 to 2021
Foreign undistributed net earnings for which no deferred taxes have been provided	6.9
Effect of unrecognized tax benefits on effective tax rate	6.3	7.0
Accrual for income tax penalties and interest	0.9	1.2
Federal and United Kingdom
Income Tax Contingency [Line Items]
Net tax loss carryforwards	19.3
State
Income Tax Contingency [Line Items]
Net tax loss carryforwards	$ 13.3

Reconciliation of Beginning and Ending Amount of Unrecognized Tax Benefits (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Sep. 30, 2011
Schedule of Unrecognized Tax Benefits [Line Items]
Balance at beginning of period	$ 7,568	$ 1,832
Additions based on tax positions related to current year	1,008	129
Reductions for tax positions of prior years	(3,190)	(760)
Acquisitions	1,546	6,367
Balance at end of period	$ 6,932	$ 7,568

Environmental Remediation Obligation (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Site Contingency [Line Items]
Accrued liabilities	$ 1,000	$ 1,000
Other non-current liabilities	18,092	18,888
Total	$ 19,092	$ 19,888

Capital Stock - Additional Information (Detail) (USD $)	1 Months Ended		12 Months Ended
Capital Stock - Additional Information (Detail) (USD $)	Aug. 23, 2011	Oct. 23, 2008	Sep. 30, 2012	Sep. 30, 2011
Shareholders Equity [Line Items]
Common stock, shares authorized			224,400,000	224,400,000
Common stock, par value			$ 0.01	$ 0.01
Preferred stock, shares authorized			149,600,000	149,600,000
Preferred stock, par value			$ 0.01	$ 0.01
Common stock, shares outstanding			52,157,225	50,829,276
Preferred stock, shares outstanding			0	0
Stock repurchase program, authorized amount	$ 100,000,000
Shares repurchased under the program			11,300
Value of common stock repurchased		$ 15,200,000	$ 846,000
Weighted average price per share		$ 30.85	$ 74.87
Treasury stock, shares		494,100	505,400	494,100

Summary of Activity, Pricing and Other Information for Rollover Option Award Activity (Detail) (2003 Stock Option Plan, USD $)	12 Months Ended
	Sep. 30, 2012
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Granted	3,870,152
Rollover Option Awards
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of Options, Outstanding, beginning of period	84,436
Number of Options, Granted
Number of Options, Exercised	(84,436)
Number of Options, Forfeited
Number of Options Exercisable at end of period
Weighted-Average Exercise Price Per Option, Outstanding, beginning of period	$ 3.47
Weighted-Average Exercise Price Per Option, Granted
Weighted-Average Exercise Price Per Option, Exercised	$ 3.47
Weighted-Average Exercise Price Per Option, Forfeited
Weighted-Average Exercise Price Per Option, Exercisable

Fair Value Measurements - Additional Information (Detail)	12 Months Ended
	Sep. 30, 2012
Carrying Amounts and Fair Values of Financial Instruments [Line Items]
Interest rate of senior subordinated debt	7.75%

Derivatives And Hedging Activities - Additional Information (Detail) (New Senior Secured Credit Facility, USD $) In Millions, unless otherwise specified	12 Months Ended
	Sep. 30, 2012	Jun. 27, 2011
New Senior Secured Credit Facility
Derivative [Line Items]
Interest rate swap, notional amount	$ 353	$ 353
Fixed rate of interest under interest rate swap	5.17%	5.17%
Interest rate swap agreements description	2.17% plus the 3% margin percentage

Accumulated Other Comprehensive Income (Loss) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Accumulated Other Comprehensive Income [Line Items]
Interest rate swap agreements, net of taxes of $3.7 million for 2012 and $2.1 million for 2011	$ (6,135)	$ (3,500)
Cumulative foreign currency translation adjustments	480	1,795
Pension liability adjustments, net of taxes of $1.8 million for 2012 and $1.0 million for 2011	(2,396)	(1,572)
Total	$ (8,051)	$ (3,277)

Accumulated Other Comprehensive Income (Loss) (Parenthetical) (Detail) (USD $) In Thousands, unless otherwise specified	Sep. 30, 2012	Sep. 30, 2011
Accumulated Other Comprehensive Income [Line Items]
Interest rate swap agreements, taxes	$ 3,700	$ 2,100
Pension liability adjustments, taxes	$ 1,800	$ 1,000

Discontinued Operations - Additional Information (Detail) (USD $)	12 Months Ended	1 Months Ended
	Sep. 30, 2011	Apr. 07, 2011 Aero Quality Sales	Mar. 09, 2011 Fastener Business
Income Statement, Balance Sheet and Additional Disclosures by Disposal Groups, Including Discontinued Operations [Line Items]
Proceeds from divestiture of business	$ 271,361,000	$ 31,800,000	$ 239,600,000
Gain (loss) on sale of discontinued operations, net of tax	22,032,000	(1,600,000)	23,600,000
Gain on sale of discontinued operations		6,200,000	56,500,000
Working capital adjustment		$ 1,800,000

Quarterly Financial Data (Unaudited) (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended								12 Months Ended
	Sep. 30, 2012	Jun. 30, 2012	Mar. 31, 2012	Dec. 31, 2011	Sep. 30, 2011	Jul. 02, 2011	Apr. 02, 2011	Jan. 01, 2011	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2010
Quarterly Financial Data [Line Items]
NET SALES									$ 1,700,208	$ 1,206,021	$ 827,654
GROSS PROFIT									945,717	661,185	473,066
Net income (loss) from discontinued operations										19,909
Net income (loss)									324,969	172,134	163,445
Net earnings (loss) per share from continuing operations-basic and diluted									$ 5.97	$ 2.80	$ 2.52
Net earnings (loss) per share from discontinued operations-basic and diluted										$ 0.37
Net earnings per share-basic and diluted									$ 5.97	$ 3.17	$ 2.52
TransDigm Group
Quarterly Financial Data [Line Items]
NET SALES	462,606	461,660	423,469	352,473	342,953	325,209	304,307	233,552
GROSS PROFIT	256,820	253,302	236,040	199,555	193,016	183,149	157,874	127,146
Net income (loss) from continuing operations					64,313	58,368	36,697	(7,153)
Net income (loss) from discontinued operations					3,082	(2,088)	19,120	(205)
Net income (loss)	$ 87,866	$ 90,446	$ 81,552	$ 65,105	$ 67,395	$ 56,280	$ 55,817	$ (7,358)	$ 324,969	$ 172,134	$ 163,445
Net earnings (loss) per share from continuing operations-basic and diluted					$ 1.20	$ 1.10	$ 0.69	$ (0.19)
Net earnings (loss) per share from discontinued operations-basic and diluted					$ 0.06	$ (0.04)	$ 0.35
Net earnings per share-basic and diluted	$ 1.63	$ 1.68	$ 1.51	$ 1.15	$ 1.26	$ 1.06	$ 1.04	$ (0.19)

Supplemental Guarantor Information - Additional Information (Detail)	12 Months Ended
	Sep. 30, 2012
Supplemental Guarantor Information [Line Items]
Interest rate of senior subordinated debt	7.75%
Senior subordinate note, due date	2018