CONSOLIDATED STATEMENTS OF CASH FLOWS - USD ($) $ in Thousands	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016
Cash flows from operating activities
Net loss	$ (16,687)	$ (4,145)	$ (34,972)	$ (21,528)
Adjustments to reconcile net loss to net cash provided by operating activities:
Provision for doubtful accounts			2,893
Depreciation and amortization			10,113	8,692
Write-off and amortization of debt issuance costs			1,383	1,317
Share-based compensation expense			1,460	1,084
Gain on disposal of property and equipment			(23)
Gain on extinguishment of convertible senior notes			(114)	(69)
Deferred income taxes				4
Changes in operating assets and liabilities, net of acquisitions:
Accounts receivable			60,229	30,495
Inventory			(5,785)	(10,924)
Income taxes receivable			(1,438)	573
Prepaid expenses and other assets			(10,898)	4,003
Accounts payable			15,322	32,330
Accrued expenses			(16,255)	(19,963)
Reserve for sales returns and allowances			(7,368)	(8,307)
Income taxes payable			(1,043)	985
Other liabilities			(265)	18
Total adjustments			48,211	40,238
Net cash provided by operating activities			13,239	18,710
Cash flows from investing activities
Purchases of property and equipment			(7,611)	(6,110)
Proceeds from sale of property and equipment			24
Net cash used in investing activities			(7,587)	(6,110)
Cash flows from financing activities
Repurchase of common stock				(11,941)
Repurchase of common stock for employee tax withholding			(12)	(844)
Repayment of credit facility borrowings			(10,000)
Repurchase of convertible senior notes			(35,614)	(2,626)
Proceeds from issuance of common stock			19,311
Net cash used in financing activities			(26,315)	(15,411)
Net decrease in cash and cash equivalents			(20,663)	(2,811)
Effect of foreign currency translation			2,197	(3,091)
Cash, cash equivalents, and restricted cash, beginning of period			86,064	102,528	$ 102,528
Cash, cash equivalents, and restricted cash, end of period	$ 67,598	$ 96,626	67,598	96,626	$ 86,064
Cash paid during the period for:
Income taxes			1,598	23
Interest			$ 4,793	$ 4,899