Consolidated Statements of Cash Flows - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Operating activities:
Net income (loss)	$ 26,144	$ 8,587	$ (80,856)
Adjustments to reconcile net income (loss) to net cash used in operating activities:
Stock-based compensation	7,686	9,492	8,207
Depreciation	1,621	1,625	1,806
Amortization of debt issuance costs and non-cash interest	791	457	569
Change in fair value of warrant liabilities	1,103	(25,332)	21,927
Change in fair value of embedded derivatives	0	14	(759)
Change in fair value of contingent consideration	(2,000)	0	0
Impairment of long-lived assets	0	838	0
Loss on sale of short-term investments	5,746	0	0
Loss on extinguishment of debt	0	1,254	0
Net gain on sale of business	(89,484)	(79,980)	0
Changes in operating assets and liabilities:
Trade accounts receivable	7,477	(2,212)	(1,022)
Inventory	1,394	(3,503)	2,950
Prepaid expenses and other current assets	(743)	(9,200)	(2,004)
Other assets	244	(4,367)	(1,747)
Accounts payable and accrued expenses	(14,220)	5,645	6,146
Deferred revenue	(8,464)	15,658	(137)
Deferred tax liability	(2,050)	0	0
Deferred rent	153	208	0
Net cash used in operating activities	(64,602)	(80,816)	(44,920)
Investing activities:
Purchases of property and equipment	(308)	(122)	(810)
Proceeds from sale of business	82,984	89,624	0
Restricted cash from sale of business	(1,502)	(8,500)	0
Proceeds of sales of short-term investments	4,371	0	0
Acquisition of business, net of cash acquired	0	(20,000)	0
Net cash provided by (used in) investing activities	85,545	61,002	(810)
Financing activities:
Proceeds from borrowings of debt and revolving credit facility, net of issuance costs	0	27,977	0
Payments on borrowings of debt	(1,450)	(40,041)	0
Proceeds from exercise of common stock options and warrants	1,441	1,506	833
Proceeds from issuance of common stock and common stock warrants, net of issuance costs	92,210	556	75,690
Net cash provided by (used in) financing activities	92,201	(10,002)	76,523
Net increase (decrease) in cash and cash equivalents	113,144	(29,816)	30,793
Cash and cash equivalents at beginning of period	42,205	72,021	41,228
Cash and cash equivalents at end of period	155,349	42,205	72,021
Supplemental disclosure of cash flow information:
Cash paid for interest	1,466	12,847	2,463
Noncash investing and financing activities:
Issuance of common stock in conjunction with acquisition	0	15,237	0
Issuance of common stock in conjunction with cashless exercise of warrants	300	0	0
Purchase of property and equipment in accounts payable	0	12	446
Change in common stock warrant liability associated with exercise of warrants	0	(916)	(79)
Warrants issued in connection with debt	$ 0	$ 558	$ 0