Capital Assets (Goodwill) (Details) $ in Thousands	3 Months Ended
	Dec. 31, 2016 USD ($)
Goodwill [Roll Forward]
Goodwill, Beginning Balance	$ 369,700
Currency translation gain (loss)	(607)
Goodwill, Ending Balance	369,093
Test [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	25,022
Currency translation gain (loss)	(557)
Goodwill, Ending Balance	24,465
Sensors [Member]
Goodwill [Roll Forward]
Goodwill, Beginning Balance	344,678
Currency translation gain (loss)	(50)
Goodwill, Ending Balance	$ 344,628