CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Retained Earnings	Accumulated Other Comprehensive Income
Balance at Dec. 31, 2015	$ 298,980	$ 215	$ 221,487	$ 76,946	$ 332
Balance (in shares) at Dec. 31, 2015		21,570,746
Increase (Decrease) in Stockholders' Equity
Net income	28,152			28,152
Other comprehensive income	1,031				1,031
Share-based compensation expense	1,831		1,831
Issuance of restricted stock, net (in shares)		218,236
Common stock issued	119,383	$ 58	119,325
Common stock issued (in shares)		5,815,051
Exercise of stock options	588		588
Exercise of stock options (in shares)		52,500
Balance at Sep. 30, 2016	449,965	$ 273	343,231	105,098	1,363
Balance (in shares) at Sep. 30, 2016		27,656,533
Balance at Dec. 31, 2016	$ 459,740	$ 274	345,138	117,049	(2,721)
Balance (in shares) at Dec. 31, 2016	27,798,283	27,798,283
Increase (Decrease) in Stockholders' Equity
Net income	$ 43,929			43,929
Other comprehensive income	5,197				5,197
Share-based compensation expense	4,246		4,246
Issuance of restricted stock, net	0		0
Issuance of restricted stock, net (in shares)		4,085
Common stock issued	464,982	$ 120	464,862
Common stock issued (in shares)		11,971,917
Goodwill adjustment	500	$ 0	500
Goodwill adjustment (in shares)		0
Repurchase of common stock	(1,259)		(1,259)
Repurchase of common stock (in shares)		0
Exercise of stock options	4,325	$ 3	4,322
Exercise of stock options (in shares)		387,741
Balance at Sep. 30, 2017	$ 981,660	$ 397	$ 817,809	$ 160,978	$ 2,476
Balance (in shares) at Sep. 30, 2017	40,162,026	40,162,026