Commitments and Contingencies Sales Return Liability (Details) - USD ($) $ in Thousands	3 Months Ended
	Apr. 01, 2017	Apr. 02, 2016
Sales return liability [Roll Forward]
Balance at beginning of year	$ 15,222	$ 20,562
Additions that reduce net sales	21,184	23,636
Deductions from reserves	(18,205)	(21,288)
Balance at end of period	$ 18,201	$ 22,910