Condensed Consolidated Statements of Cash Flows - USD ($) $ in Thousands	6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016
CASH FLOWS FROM OPERATING ACTIVITIES:
Net loss	$ (34,575)	$ (43,125)
Adjustments to reconcile loss to net cash used in operating activities:
Depreciation and amortization	38	79
Loss on sale of fixed assets		48
Stock-based compensation	6,976	6,962
Amortization of debt discount and debt issuance costs	1,147	5,038
Amortization of intangible asset	323	322
Gain on change in fair value of derivative liabilities		(4,560)
Deferred income taxes		(1,846)
Changes in assets and liabilities:
Accounts receivable, net	(17,490)	(3,813)
Inventory	(4,307)	(1,321)
Prepaid and other current assets	4,907	(2,324)
Other long-term assets	568
Accrued interest payable	(3,828)	(1,416)
Deferred revenue	(336)	1,470
Accounts payable and other current liabilities	21,709	10,773
Other long-term liabilities	448	(67)
Net cash used in operating activities	(24,420)	(33,780)
CASH FLOWS FROM INVESTING ACTIVITIES:
Purchases of equipment	(12)	(21)
Net cash used in investing activities	(12)	(21)
CASH FLOWS FROM FINANCING ACTIVITIES:
Proceeds from issuance of exchangeable debt	30,000
Payment of debt issuance costs	(1,207)
Proceeds from exercise of stock options, net of transaction costs	396	124
Repurchase of exchangeable senior notes	(15,107)
Taxes paid related to stock-based awards	(2,437)	(793)
Net cash provided by (used in) financing activities	11,645	(669)
NET DECREASE IN CASH AND CASH EQUIVALENTS	(12,787)	(34,470)
CASH AND CASH EQUIVALENTS, BEGINNING OF PERIOD	98,251	106,961
CASH AND CASH EQUIVALENTS, END OF PERIOD	85,464	72,491
Cash paid during the year for:
Interest	7,546	7,668
Income taxes	$ 778	$ 767