Stockholders' Equity (Deficit), Series A Convertible Preferred Stock (Details) - Series A Convertible Preferred Stock [Member] - USD ($) $ in Millions	1 Months Ended	6 Months Ended
	Dec. 31, 2015	Jun. 30, 2017	Dec. 31, 2016
Series A Convertible Preferred Stock [Abstract]
Shares issued (in shares)	28,884,540
Proceeds from sale of stock	$ 100.0
Preferred stock, shares authorized (in shares)		28,884,540	28,884,540
Preferred stock, shares issued (in shares)		28,884,540	28,884,540
Preferred stock, shares outstanding (in shares)		28,884,540	28,884,540
Conversion ratio		convertible 1:1 into common stock