Stockholders' Equity - Private Placement (Details 3) - Private Placement $ / shares in Units, $ in Millions	1 Months Ended	12 Months Ended
	Jan. 31, 2015 USD ($) shareholder $ / shares shares	Dec. 31, 2015 shares
Sale of stock
Proceeds from the issuance of common stock, net | $	$ 19.3
Stockholders affiliated with members of Board of Directors
Sale of stock
Proceeds from the issuance of common stock, net | $	$ 9.5
Common stock
Sale of stock
Common stock issued (in shares) | shares	3,400,000	3,418,804
Share price (in dollars per share) | $ / shares	$ 5.85
Common stock | Stockholders affiliated with members of Board of Directors
Sale of stock
Number of stockholders affiliated with members of Board of Directors who purchased shares | shareholder	2
Common stock issued (in shares) | shares	1,623,932