Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014	Dec. 31, 2013
Current assets
Cash and cash equivalents	$ 65,565	$ 51,204
Marketable investment securities	98,626	129,270
Accounts receivable	48,854	41,242
Inventory	36,815	30,035
Prepaid expenses	5,225	5,621
Other current assets	1,360	1,380
Total current assets	256,445	258,752
Property and equipment, net	5,786	4,402
Goodwill	9,429	9,429
Intangibles, net	17,505	19,301
Debt issuance costs, net of accumulated amortization of $601 and $716, respectively	251	338
Other long-term assets	201	0
Total assets	289,617	292,222
Current Liabilities
Accounts payable	21,810	10,919
Accrued expenses and other current liabilities	19,301	17,037
Accrued research and development expenses	3,408	3,541
Accrued interest expense	862	1,620
Convertible notes payable	0	16,545
Current portion of non-recourse debt	10,252	8,752
Total current liabilities	55,633	58,414
Non-recourse debt, less current portion	89,754	123,635
Other liabilities	10,405	5,283
Total liabilities	155,792	187,332
Commitments and contingencies (notes 8, 9 and 16)
Stockholders' equity:
Preferred stock, $0.001 par value. Authorized 5,000,000 shares; issued and outstanding no shares	0	0
Common stock, $0.001 par value. Authorized 175,000,000 shares; issued and outstanding 107,103,262 shares and 102,613,780 shares, respectively	107	103
Additional paid-in capital	1,167,385	1,127,420
Accumulated other comprehensive (loss) income	(2,273)	56
Accumulated deficit	(1,031,394)	(1,022,689)
Total stockholders' equity	133,825	104,890
Total liabilities and stockholders' equity	$ 289,617	$ 292,222