ACCRUED LIABILITIES (Details) - USD ($) $ in Thousands	Sep. 30, 2018	Dec. 31, 2017
Payables and Accruals [Abstract]
Accrued marketing expenses	$ 13,446	$ 25,959
Sales and other taxes payable	20,254	2,363
Accounts payable accruals	16,393	16,614
Allowance for returns	12,448	17,391
Other accrued expenses	4,954	3,920
Accrued compensation and other related costs	16,200	10,716
Accrued freight	6,754	5,040
Accrued loss contingencies	10,304	608
Total accrued liabilities	$ 100,753	$ 82,611