Revenue Recognition - Unbilled Receivables (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 01, 2016	Oct. 03, 2015	Oct. 01, 2016	Oct. 03, 2015	Jan. 02, 2016
Roll forward of the unbilled receivables allowance
Balance at beginning of period			$ 2,354	$ 2,233	$ 2,233
Increases to reserves			2,199		2,832
Amounts written off			(2,077)		(2,711)
Effects of foreign currency translation			(2)
Balance at end of period	$ 2,474		2,474		$ 2,354
Reimbursable expenses	$ 8,969	$ 8,400	$ 25,510	$ 24,719