Business Segment Information - Additional Information (Detail) - Segment	10 Months Ended	12 Months Ended
	Oct. 02, 2015	Sep. 29, 2017	Sep. 30, 2016
Segment Reporting Information [Line Items]
Number of reporting segments		3
U.S. Government
Segment Reporting Information [Line Items]
Sales as a percentage of segment sales	2.90%	3.50%	3.10%
Advanced Materials | Operating Segments | U.S. Government
Segment Reporting Information [Line Items]
Sales as a percentage of segment sales	9.90%	9.60%	9.80%
Avionics & Controls | Operating Segments | U.S. Government
Segment Reporting Information [Line Items]
Sales as a percentage of segment sales	1.10%	3.00%	2.00%