Common Stock and Stockholders' Equity - Warrants (Details) - Common stock warrants $ / shares in Units, $ in Millions			1 Months Ended
	Jan. 31, 2017 $ / shares shares	Dec. 09, 2016 $ / shares shares	Jan. 31, 2017 $ / shares shares	Dec. 31, 2016 $ / shares shares	Jul. 31, 2016 USD ($) item $ / shares shares	Mar. 31, 2017 shares
Warrants
Number of shares issued upon exercise of warrants			138,903	107,931
Cashless exercise of warrants (in shares)			399,347	399,347
Exercise price of warrants (in dollars per share) | $ / shares	$ 13.50		$ 13.50	$ 13.50
Warrants outstanding (in shares)						0
Affiliates of SVB
Warrants
Number of warrants issued					798,694
Number of shares that may be exercised from warrants					798,694
Number of shares issued upon exercise of warrants	138,903	107,931
Cashless exercise of warrants (in shares)	399,347	399,347
Exercise price of warrants (in dollars per share) | $ / shares	$ 13.50	$ 13.50	$ 13.50		$ 13.50
Number of affiliates of lender granted warrants | item					2
Term of warrants					10 years
Fair value of warrants outstanding | $					$ 7.7
Warrants outstanding (in shares)				399,347		0