Summary of Significant Accounting Policies (Other Current Liabilities) (Details) - USD ($) $ in Thousands	Dec. 31, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accounts payable	$ 12,846	$ 10,222
Accrued promotional expenses	45,579	35,900
Accrued excise and payroll taxes payable, net	13,849	18,653
Accrued interest	31,624	35,756
Commissions payable	25,615	18,378
Accrued salaries and benefits	27,104	29,464
Contract liabilities	7,633	9,358
Allowance for sales returns	7,356	7,785
Other current liabilities	27,331	23,801
Total other current liabilities	$ 198,937	$ 189,317