Discontinued Operations Income (Loss) Net of Tax (Detail) - USD ($) $ in Thousands	3 Months Ended			9 Months Ended
	Jul. 01, 2016	Jun. 26, 2015	[1]	Jul. 01, 2016	Jun. 26, 2015	[1]
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net Sales	$ 4,033	$ 21,408		$ 18,867	$ 67,406
Operating earnings (loss)	(7,414)	(1,522)		(14,630)	(24,081)
Tax expense (benefit)	1,276	(964)		863	(3,047)
Income (loss) from discontinued operations	(8,690)	(558)	[2]	(15,493)	(21,034)	[2]
Included in Operating Earnings (Loss):
Gain (loss) on net assets held for sale	(4,323)	(1,316)		(7,895)	(15,763)	[2]
Avionics & Controls
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net Sales	3,577	11,248		13,638	38,839
Operating earnings (loss)	(1,184)	(1,196)		785	(12,591)
Tax expense (benefit)	570	(869)		1,256	(958)
Income (loss) from discontinued operations	(1,754)	(327)		(471)	(11,633)
Included in Operating Earnings (Loss):
Gain (loss) on net assets held for sale	(2,411)	323		(2,355)	(11,116)
Sensors & Systems
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net Sales	0	7,577		0	19,834
Operating earnings (loss)	(71)	1,352		(378)	3,101
Tax expense (benefit)	(83)	(56)		(83)	616
Income (loss) from discontinued operations	12	1,408		(295)	2,485
Included in Operating Earnings (Loss):
Gain (loss) on net assets held for sale	0	(622)		0	(622)
Advanced Materials
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net Sales	456	2,583		5,229	8,733
Operating earnings (loss)	(5,908)	(1,687)		(14,775)	(12,908)
Tax expense (benefit)	876	(39)		(223)	(2,115)
Income (loss) from discontinued operations	(6,784)	(1,648)		(14,552)	(10,793)
Included in Operating Earnings (Loss):
Gain (loss) on net assets held for sale	(1,912)	(1,017)		(5,540)	(4,025)
Other
Income Statement Balance Sheet And Additional Disclosures By Disposal Groups Including Discontinued Operations [Line Items]
Net Sales	0	0		0	0
Operating earnings (loss)	(251)	9		(262)	(1,683)
Tax expense (benefit)	(87)	0		(87)	(590)
Income (loss) from discontinued operations	(164)	9		(175)	(1,093)
Included in Operating Earnings (Loss):
Gain (loss) on net assets held for sale	$ 0	$ 0		$ 0	$ 0

[1] recast

[2] (Recast)