Earnings Per Share - Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Diluted earnings per share
Net income available for common stockholders, net of dividends and undistributed earnings allocated to participating securities	$ 32,171	$ 20,887
Weighted average shares of common stock outstanding
Issued and outstanding	38,539,091	34,964,312
Weighted average number of shares of common stock outstanding	38,539,091	35,339,585
Diluted Earnings per share	$ 0.83	$ 0.59
Anti-dilutive shares excluded from computation of EPS	743,096	0
Class A
Weighted average shares of common stock outstanding
Issued and outstanding	38,539,091	34,964,312
2015 Management Incentive Plan | Class A
Weighted average shares of common stock outstanding
Issuable pursuant to 2015 Management Incentive Plan		375,273