CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Total	Common Stock	Additional Paid-in Capital	Accumulated Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Balance at Dec. 31, 2014	$ 199,592	$ 169	$ 147,474	$ 51,431	$ 518
Balance (in shares) at Dec. 31, 2014		16,903,884
Increase (Decrease) in Stockholders' Equity
Net Income	25,515			25,515
Other comprehensive income (loss)	(186)				(186)
Share-based compensation expense	1,165		1,165
Issuance of restricted stock, net (in shares)		60,000
Issuance of common stock	72,252	$ 45	72,207
Issuance of common stock (in shares)		4,480,645
Warrants exercised	689	$ 1	688
Warrants exercised (in shares)		125,316
Repurchase of common stock	(116)	$ 0	(116)
Repurchase of common stock (in shares)		(7,165)
Exercise of stock options	69	$ 0	69
Exercise of stock options (in shares)		8,066
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	40,103			40,103
Other comprehensive income (loss)	(3,053)				(3,053)
Share-based compensation expense	2,729		2,729
Issuance of restricted stock, net	0
Issuance of restricted stock, net (in shares)		296,236
Issuance of common stock	119,383	$ 58	119,325
Issuance of common stock (in shares)		5,815,051
Goodwill adjustment	379		379
Repurchase of common stock	(126)		(126)
Repurchase of common stock (in shares)		0
Exercise of stock options	1,345	$ 1	1,344
Exercise of stock options (in shares)		116,250
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	$ 60,100			60,100
Other comprehensive income (loss)	3,136				3,136
Share-based compensation expense	5,809		5,809
Issuance of restricted stock, net	0
Issuance of restricted stock, net (in shares)		166,397
Issuance of common stock	709,377	$ 181	709,196
Issuance of common stock (in shares)		17,954,274
Goodwill adjustment	500		500
Repurchase of common stock	(1,258)		(1,258)
Repurchase of common stock (in shares)		(21,537)
Exercise of stock options	4,592	$ 3	4,589
Exercise of stock options (in shares)		347,633
Balance at Dec. 31, 2017	$ 1,241,996	$ 458	$ 1,063,974	$ 177,149	$ 415
Balance (in shares) at Dec. 31, 2017	46,245,050	46,245,050