Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Jan. 02, 2016	Jan. 03, 2015
Allowance for Doubtful Accounts [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	$ 1,039	$ 739	$ 425
Additions charged to costs and expenses	1,224	1,577	729
Deductions from reserves	(1,379)	(1,277)	(415)
Balance at end of period	884	1,039	739
Allowance for Sales Returns [Member]
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at beginning of period	20,562	15,262	9,433
Additions charged to costs and expenses	71,958	84,265	78,890
Deductions from reserves	(77,298)	(78,965)	(73,061)
Balance at end of period	$ 15,222	$ 20,562	$ 15,262