Summary of Significant Accounting Policies (Other Current Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2021	Dec. 31, 2020
Accounting Policies [Abstract]
Accounts payable	$ 10,718	$ 12,846
Accrued promotional expenses	49,269	45,579
Accrued excise and payroll taxes payable, net	22,973	13,849
Accrued interest	30,998	31,624
Commissions payable	38,832	25,615
Accrued salaries and benefits	25,517	27,104
Contract liabilities	7,507	7,633
Allowance for sales returns	7,414	7,356
Other current liabilities	30,270	27,331
Total other current liabilities	$ 223,498	$ 198,937