Stock-Based Compensation - Summary of Common Stock Option Activity (Details) - $ / shares	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2016
Number of Shares
Options outstanding at December 31 (shares)	835,786	840,298
Options granted (shares)	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	(9,288)	0
Options forfeited (shares)	0	(4,512)
Options outstanding at September 30 (shares)	826,498	835,786
Options exercisable at September 30 (shares)	826,498	44,442
Weighted-Average Exercise Price per share
Options outstanding at December 31 (in dollars per share)	$ 11.00	$ 11.00
Options granted (in dollars per share)	0.00	0.00
Share-based Compensation Arrangements by Share-based Payment Award, Options, Exercises in Period, Weighted Average Exercise Price	11.00	0.00
Options forfeited (in dollars per share)	0.00	11.00
Options outstanding at September 30 (in dollars per share)	11.00	11.00
Options exercisable at September 30 (in dollars per share)	$ 11.00	$ 11.00