Stock-Based Compensation - Restricted Stock (Details) - Restricted Stock - USD ($) $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vested in period, fair value	$ 3,300
Vested in period (in shares)	246,690	0
Number of Shares (in shares)
Outstanding at beginning of period (in shares)	600,025
Granted (in shares)	381,952
Forfeited (in shares)	0
Vested (in shares)	(246,690)	0
Outstanding at end of period (in shares)	735,287
Weighted- Average Grant Date Fair Value (in dollars per share)
Outstanding at beginning of period (in dollars per share)	$ 13.38
Granted (in dollars per share)	15.11
Forfeited (in dollars per share)	0
Vested (in dollars per share)	13.35
Outstanding at end of period (in dollars per share)	$ 14.29
Aggregate intrinsic value	$ 13,331		$ 10,542
Unrecognized compensation expense	$ 7,600
Unrecognized compensation expense, period for recognition (years)	1 year 9 months 18 days
Executive Officer
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)	3 years
Non-employee Members, Board of Directors
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Award vesting period (years)	1 year