Other Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Sep. 24, 2016
Other Liabilities Disclosure [Abstract]
Customer prepayments & deposits	$ 3,133	$ 3,115
Total other liabilities, current	3,133	3,115
Foreign exchange contract liabilities		12
Other payables, net of current portion	2,614	3,454
Asset retirement obligations	659	921
Pension liability	9,501	7,975
Total other liabilities, long-term	12,774	12,362
Other liabilities	$ 15,907	$ 15,477