Summary of Significant Accounting Policies (Other Current Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2020	Dec. 31, 2019
Accounting Policies [Abstract]
Accounts payable	$ 11,962	$ 10,222
Accrued promotional expenses	45,966	35,900
Accrued excise and payroll taxes payable, net	2,817	18,653
Accrued interest	33,159	35,756
Commissions payable	28,972	18,378
Accrued salary and benefits	19,059	29,464
Contract liabilities	9,725	9,358
Allowance for sales returns	7,857	7,785
Other current liabilities	34,511	23,801
Total other current liabilities	$ 194,028	$ 189,317