Other Liabilities (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Sep. 24, 2016
Other liabilities [Line Items]
Customer prepayments & deposits	$ 3,913	$ 3,115
Total other liabilities, current	3,913	3,115
Foreign exchange contract liabilities	0	12
Other payables, net of current portion	2,869	3,454
Asset retirement obligations	741	921
Pension liability	8,505	7,975
Total other liabilities, long-term	12,115	12,362
Other Liabilities	$ 16,028	$ 15,477