Schedule II-Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
	Dec. 27, 2014	Dec. 31, 2016	Dec. 26, 2015	Dec. 27, 2014
Movement in Valuation and Qualifying Accounts
Balance at beginning of period			$ 9,922
Balance at close of period	$ 9,922			$ 9,922
Allowance for doubtful receivables
Movement in Valuation and Qualifying Accounts
Balance at beginning of period		$ 21,008	9,922	10,369
Charged to profit and loss	1,780	1,273	12,420
Currency Translation Adjustment	(308)	(734)	(1,143)
Deductions from reserves		2,556	191	1,919
Balance at close of period	9,922	18,991	21,008	9,922
Allowance for deferred income tax asset valuation
Movement in Valuation and Qualifying Accounts
Balance at beginning of period		90,837	104,487	107,767
Charged to profit and loss		9,888	1,267	958
Currency Translation Adjustment		(18,129)	(14,917)	(4,238)
Deductions from reserves		673	0	0
Balance at close of period	$ 104,487	$ 81,923	$ 90,837	$ 104,487