Earnings per Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Basic earnings per share
Net income	$ 18,027	$ 7,926
Average common stock outstanding	46,951,829	38,839,284
Net income per share	$ 0.38	$ 0.2
Diluted earnings per share
Net income	$ 18,027	$ 7,926
Average common stock outstanding	46,951,829	38,839,284
Add: Dilutive effect of employee restricted stock and stock options	736,559	659,551
Average diluted stock outstanding	47,688,388	39,498,835
Net income per share	$ 0.38	$ 0.2