Summary of Significant Accounting Policies (Other Current Liabilities) (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Jan. 01, 2019	Dec. 31, 2018
Accounting Policies [Abstract]
Accounts payable	$ 9,852		$ 13,144
Accrued promotional expenses	26,586		37,940
Accrued excise and payroll taxes payable, net	16,044		14,612
Accrued interest	32,375		38,673
Commissions payable	26,698		12,975
Accrued salary and benefits	21,231		30,228
Contract liabilities	8,159	$ 7,071	0
Allowance for sales returns	7,042		6,935
Other current liabilities	27,799		25,831
Total other current liabilities	$ 175,786		$ 180,338