Consolidated Statements of Stockholders' Equity (Deficit) (Parenthetical) - USD ($)	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014
Stock issuance costs	$ 28,000
Initial Public Offering
Stock issuance costs	$ 16,800,000
Series C convertible preferred stock
Stock issuance costs		$ 800,000
Common Class A
Stock issuance costs		$ 200,000