Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 12,201	$ 13,105	$ 10,867
Additions Charged to Costs and Expenses	30,738	34,207	32,718
Deductions	31,581	35,111	30,480
Balance at End of Period	11,358	12,201	13,105
Doubtful accounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	112	37	192
Additions Charged to Costs and Expenses	0	75	31
Deductions	24	0	186
Balance at End of Period	88	112	37
Cash discounts
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	367	415	241
Additions Charged to Costs and Expenses	25,237	25,616	25,801
Deductions	25,331	25,664	25,627
Balance at End of Period	273	367	415
Deferred tax valuation allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	3,900	4,933	6,014
Additions Charged to Costs and Expenses	539	0	0
Deductions	0	1,033	1,081
Balance at End of Period	4,439	3,900	4,933
Sales returns
Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	7,822	7,720	4,420
Additions Charged to Costs and Expenses	4,962	8,516	6,886
Deductions	6,226	8,414	3,586
Balance at End of Period	$ 6,558	$ 7,822	$ 7,720