Schedule II - Valuation and Qualifying Accounts (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	$ 10,070	$ 11,518	$ 9,694
Additions Charged to Costs and Expenses	35,842	30,284	33,436
Deductions	31,751	31,732	31,612
Balance at End of Period	14,161	10,070	11,518
Doubtful accounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	674	449	33
Additions Charged to Costs and Expenses	0	246	429
Deductions	674	21	13
Balance at End of Period	0	674	449
Cash discounts
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	319	317	365
Additions Charged to Costs and Expenses	28,046	25,970	28,154
Deductions	28,031	25,968	28,202
Balance at End of Period	334	319	317
Deferred tax valuation allowance
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	1,292	3,817	3,664
Additions Charged to Costs and Expenses	5,179	0	153
Deductions	0	2,525	0
Balance at End of Period	6,471	1,292	3,817
Sales returns
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Balance at Beginning of Period	7,785	6,935	5,632
Additions Charged to Costs and Expenses	2,617	4,068	4,700
Deductions	3,046	3,218	3,397
Balance at End of Period	$ 7,356	$ 7,785	6,935
Accounting Standards Update 2014-09 | Sales returns
SEC Schedule, 12-09, Movement in Valuation Allowances and Reserves [Roll Forward]
Additions Charged to Costs and Expenses			$ 2,525