Related-Party Transactions (Details) - USD ($) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Apr. 30, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016	Dec. 31, 2016
Related Party Transactions [Abstract]
Deferred compensation		$ 4,066		$ 4,066		$ 27,322
Fair value of common stock		23		23		$ 839
Paid out	$ 23,400
Deferred compensation expense		$ 16	$ 1,800	$ 221	$ 1,100