Business Segment Information (Financial Information By Reportable Segment) (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2016 USD ($) segment	Jan. 02, 2016 USD ($)
Segment Reporting Information [Line Items]
Number of operating segments | segment	2
Revenues	$ 199,279	$ 140,501
Total income from operations	10,290	13,601
Test [Member]
Segment Reporting Information [Line Items]
Revenues	131,126	118,810
Total income from operations	11,716	10,387
Sensors [Member]
Segment Reporting Information [Line Items]
Revenues	68,153	21,691
Total income from operations	$ (1,426)	$ 3,214