Stockholders' Deficit (Details 3)		3 Months Ended	9 Months Ended
	Jul. 02, 2015 USD ($) item	Sep. 30, 2015 USD ($) shares	Sep. 30, 2015 USD ($) shares	Jun. 08, 2015 shares	Dec. 31, 2014 shares
Stockholders' Deficit
Number of common shares authorized for issuance | shares		350,000,000	350,000,000	350,000,000	200,000,000
Common stock issued in connection with exercise of warrants (in shares) | shares		189,412
Proceeds from issuance of warrants		$ 1,000,000
Employee stock option exercised | shares		248,387
Common stock issued in connection with exercise of stock options		$ 1,100,000	$ 1,079,000
Shelf Registration
Stockholders' Deficit
Minimum number of offerings | item	1
Minimum number of securities | item	1
Maximum offering price	$ 250,000,000