Changes in Goodwill by Segment (Detail) - USD ($) $ in Thousands	12 Months Ended
Sep. 29, 2017	Sep. 30, 2016
Goodwill [Line Items]
Goodwill, Beginning Balance	$ 1,024,667	$ 1,041,991
Goodwill adjustments		(1,732)
Foreign currency translation adjustment	28,906	(15,592)
Goodwill, Ending Balance	1,053,573	1,024,667
Avionics & Controls
Goodwill [Line Items]
Goodwill, Beginning Balance	442,794	450,599
Goodwill adjustments		(1,732)
Foreign currency translation adjustment	13,224	(6,073)
Goodwill, Ending Balance	456,018	442,794
Sensors & Systems
Goodwill [Line Items]
Goodwill, Beginning Balance	385,567	387,707
Goodwill adjustments		0
Foreign currency translation adjustment	14,266	(2,140)
Goodwill, Ending Balance	399,833	385,567
Advanced Materials
Goodwill [Line Items]
Goodwill, Beginning Balance	196,306	203,685
Goodwill adjustments		0
Foreign currency translation adjustment	1,416	(7,379)
Goodwill, Ending Balance	$ 197,722	$ 196,306

Amount after accumulated impairment loss of an asset representing future economic benefits arising from other assets acquired in a business combination that are not individually identified and separately recognized.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=6388280&loc=d3e13770-109266

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 45
-Paragraph 5
-URI http://asc.fasb.org/extlink&oid=77989000&loc=SL49117168-202975

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Name Accounting Standards Codification
-Topic 350
-SubTopic 20
-Section 50
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=35741047&loc=d3e13816-109267

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