Consolidated Statements of Shareholders’ Equity - USD ($) $ in Thousands	Total	Common Stock [Member]	Capital Surplus [Member]	Retained Earnings [Member]	Accumulated Other Comprehensive Income (Loss), Net of Tax [Member]	Treasury Stock [Member]
Balance at beginning of period at Dec. 31, 2015		$ 33,625	$ 337,349	$ 152,820	$ 3,353	$ (12,388)
Balance at beginning of period, shares at Dec. 31, 2015		33,625,162				1,413,777
Issuance of common stock		$ 2,549	69,906
Issuance of common stock ,shares		2,549,469
Issuance of restricted shares		$ 97	(97)
Issuance of restricted shares, shares		96,749
Forfeitures of restricted shares		$ (3)	3
Forfeitures of restricted shares, shares		(3,000)
Exercise of stock options		$ 4	73
Exercise of stock options, shares		3,805
Share-based compensation			492
Net income	$ 12,317			12,317
Dividends on common shares				(1,742)
Other comprehensive income (loss) during the period	3,058				3,058
Purchase of treasury shares						$ (588)
Purchase of treasury shares,shares						20,954
Total Shareholders’ Equity at Mar. 31, 2016	600,828	$ 36,272	407,726	163,395	6,411	$ (12,976)
Balance at end of period, shares at Mar. 31, 2016		36,272,185				1,434,731
Balance at beginning of period at Dec. 31, 2016	646,437	$ 36,378	410,276	214,454	(1,058)	$ (13,613)
Balance at beginning of period, shares at Dec. 31, 2016		36,377,807				1,456,333
Issuance of common stock		$ 2,141	92,359
Issuance of common stock ,shares		2,141,072
Issuance of restricted shares		$ 68	(68)
Issuance of restricted shares, shares		67,721
Forfeitures of restricted shares		$ 0	0
Forfeitures of restricted shares, shares		0
Exercise of stock options		$ 16	303
Exercise of stock options, shares		16,349
Share-based compensation			673
Net income	21,153			21,153
Dividends on common shares				(3,713)
Other comprehensive income (loss) during the period	(151)				(151)
Purchase of treasury shares						$ (1,002)
Purchase of treasury shares,shares						17,902
Total Shareholders’ Equity at Mar. 31, 2017	$ 758,216	$ 38,603	$ 503,543	$ 231,894	$ (1,209)	$ (14,615)
Balance at end of period, shares at Mar. 31, 2017		38,602,949				1,474,235