Significant Accounting Policies (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($) customer	Dec. 31, 2014 USD ($) customer	Dec. 31, 2013 USD ($)
Movement in Valuation Allowances and Reserves [Roll Forward]
Marketing and advertising expense	$ 54,800	$ 42,600	$ 35,800
Prepaid advertising	$ 1,500	$ 1,400
Minimum
Significant Accounting Policies [Line Items]
Product Warranty Period	30 days
Furniture, equipment and information systems [Member] | Minimum
Significant Accounting Policies [Line Items]
Estimated useful life (in years)	3 years
Furniture, equipment and information systems [Member] | Maximum
Significant Accounting Policies [Line Items]
Estimated useful life (in years)	7 years
Customer Concentration Risk | Consolidated Net Sales [Member]
Significant Accounting Policies [Line Items]
Number of major customers | customer	1	1,000
Customer Concentration Risk | Customer A [Member] | Consolidated Net Sales [Member] | Minimum
Significant Accounting Policies [Line Items]
Concentration risk, percentage	10.00%	10.00%
Customer Concentration Risk | Customer A [Member] | Consolidated Net Sales [Member] | Maximum
Significant Accounting Policies [Line Items]
Concentration risk, percentage	15.00%	15.00%
Sales Discounts and Returns Allowance
Movement in Valuation Allowances and Reserves [Roll Forward]
Beginning Balance	$ 4,296	$ 4,106	4,990
Charges to reserve	16,700	15,285	13,345
Reductions for sales discounts and returns	(15,569)	(15,095)	(14,229)
Business acquisition (Note 2)	250	0	0
Ending Balance	5,677	4,296	$ 4,106
Fair Value, Measurements, Recurring
Significant Accounting Policies [Line Items]
Cash Equivalents	$ 734	$ 24,068