Accrued Expenses And Other Current Liabilities (Schedule Of Accrued Expenses & Other Current Liabilities) (Details) - USD ($) $ in Thousands	Mar. 31, 2017	Dec. 31, 2016
Payables and Accruals [Abstract]
Accrued compensation and benefits	$ 18,690	$ 20,898
Fulfillment, freight, and duties	12,372	14,572
Professional services	10,257	10,900
Sales/use and value added tax payable	4,447	4,978
Accrued rent and occupancy	8,102	7,335
Royalties payable and deferred revenue	6,553	7,475
Other	13,095	12,124
Total accrued expenses and other current liabilities	$ 73,516	$ 78,282