Schedule II - Valuation and Qualifying Accounts - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands		12 Months Ended
		Dec. 31, 2016		Dec. 26, 2015		Dec. 27, 2014
Allowance for Doubtful Accounts [Member]
Balance		$ 71		$ 179		$ 330
Additions (Reductions) Not Charged to Expense	[1]	(4)		1		(1)
Additions (Reductions) Charged (Credited) to Expense		13		19		(126)
Deductions/Write-offs		(1)		128		24
Balance		81		71		179
Inventory Valuation Reserve [Member]
Balance		26,653		27,851		35,221
Additions (Reductions) Not Charged to Expense		1,789	[2]	(648)	[1]	(762)	[1]
Additions (Reductions) Charged (Credited) to Expense		1,125		2,409		2,624
Deductions/Write-offs		8,082		2,959		9,232
Balance		$ 21,485		$ 26,653		$ 27,851

[1] Changes in reserve balances resulting from foreign currency impact.

[2] Changes in reserve balances resulting from foreign currency impact and reclassifications from other reserves.