Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Income/(Loss) (numerator)
Net income applicable to earnings per share									$ 40,103	$ 25,515	$ 16,616
Basic earnings per share: Income available to common stockholders	$ 11,953	$ 9,227	$ 10,369	$ 8,554	$ 8,065	$ 7,837	$ 7,825	$ 1,789	40,103	25,515	16,616
Diluted earnings per share: Income available to common stockholders									$ 40,103	$ 25,515	$ 16,616
Shares (denominator)
Basic income available to common stockholders (in shares)									26,931,634	21,156,668	17,046,660
Effect of dilutive stock options (in shares)									507,525	332,030	297,317
Diluted income available to common stockholders plus assumed conversions (in shares)									27,439,159	21,488,698	17,343,977
Per Share Amount
Basic income available to common stockholders (in dollars per share)	$ 0.44	$ 0.34	$ 0.38	$ 0.33	$ 0.38	$ 0.36	$ 0.36	$ 0.09	$ 1.49	$ 1.21	$ 0.97
Diluted income available to common stockholders plus assumed conversions (in dollars per share)	$ 0.43	$ 0.33	$ 0.37	$ 0.33	$ 0.37	$ 0.36	$ 0.36	$ 0.09	$ 1.46	$ 1.19	$ 0.96