Consolidated Balance Sheets (USD $) In Thousands, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013
Current assets:
Cash and cash equivalents	$ 12,252	$ 32,980
Marketable securities	46,615	49,211
Accounts receivable, net	9,725	5,054
Interest receivable	636	483
Inventories	7,957	7,152
Prepaid expenses and other current assets	2,559	2,052
Deferred financing costs, current	185	229
Total current assets	79,929	97,161
Property and equipment, net	2,648	2,554
Intangible assets, net	2,157	1,158
Long term marketable securities	11,662	8,756
Other non-current assets	360	361
Deferred financing costs, long-term	764	1,005
Total assets	97,520	110,995
Current liabilities:
Accounts payable and accrued expenses	14,658	18,314
Deferred product revenue, net	12,271	7,882
Deferred licensing revenue	173	204
Total current liabilities	27,102	26,400
Deferred licensing revenue, net of current portion	1,381	1,417
Convertible notes, net of discount	28,358	34,393
Other non-current liabilities	2,101	2,677
Derivative liabilities	9,565	12,644
Total liabilities	68,507	77,531
Stockholders' equity:
Common stock, $0.001 par value, 130,000,000 shares authorized at March 31, 2014 and December 31, 2013; 42,046,083 and 39,983,437 shares issued and outstanding at March 31, 2014 and December 31, 2013, respectively	42	40
Additional paid-in capital	223,041	211,952
Accumulated other comprehensive income	1
Accumulated deficit	(194,071)	(178,528)
Total stockholders' equity	29,013	33,464
Total liabilities and stockholders' equity	$ 97,520	$ 110,995