Accrued Expenses (Details) - USD ($) $ in Thousands	Dec. 31, 2016	Dec. 31, 2015
Accrued Expenses [Abstract]
Accrued sales force commissions and other payments	$ 126,153	$ 166,273
Accrued other taxes	31,748	35,922
Accrued payroll and other employee expenses	25,412	24,390
Accrued payable to vendors	28,456	40,914
Accrued royalties	4,767	9,701
Sales return reserve	6,125	7,752
Deferred revenue	13,494	6,644
Other	38,868	19,320
Total accrued expenses	$ 275,023	$ 310,916