Summary Stockholders' Equity (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2015 USD ($)
Balance at the beginning	$ 40,699
Balance at the ending	78,587
Common Stock
Balance at the beginning	43
Equity issued on note conversion	6
Balance at the ending	49
Additional Paid-in Capital
Balance at the beginning	230,263
Share-based compensation	3,011
Issuance of ESPP shares	324
Exercise of stock options	743
Equity issued on note conversion	26,013
Exercise of warrants	652
Balance at the ending	$ 261,006