Summary of Significant Accounting Policies (Other Current Liabilities) (Details) - USD ($) $ in Thousands	Sep. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Accounts payable	$ 14,191		$ 13,144
Accrued promotional expenses	40,977		37,940
Accrued excise and payroll taxes payable, net	5,065		14,612
Accrued interest	28,116		38,673
Commissions payable	17,730		12,975
Accrued salary and benefits	25,518		30,228
Contract liabilities	7,416	$ 7,071	0
Allowance for sales returns	6,617		6,935
Other current liabilities	29,092		25,831
Total other current liabilities	$ 174,722		$ 180,338