Consolidated Statements of Changes in Shareholders Equity - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Retained Earnings Cumulative effect of accounting changes from adoption	Retained Earnings	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Cumulative effect of accounting changes from adoption	Total
Beginning balance at Dec. 31, 2017	$ 257	$ 343,249		$ 118,353	$ (15,256)	$ (389)		$ 446,214
Beginning balance, shares at Dec. 31, 2017	25,731,504				(898,272)
Net income				47,289				47,289
Dividends on common stock, $0.20, $0.40 and $0.40 per share for the year ended December 31, 2018, 2019 and 2020, respectively				(5,016)				(5,016)
Stock-based compensation expense		1,601						1,601
Vesting of restricted stock, net of shares withheld for employee tax liabilities	$ 1	(172)						(171)
Vesting of restricted stock, net of shares withheld for employee tax liabilities (in shares)	46,189
Other comprehensive income (loss), net of tax						(2,586)		(2,586)
Exercise of stock options		(181)			$ 475			294
Exercise of stock options (in shares)					28,000
Ending balance at Dec. 31, 2018	$ 258	344,497		160,626	$ (14,781)	(2,975)		487,625
Ending balance, shares at Dec. 31, 2018	25,777,693				(870,272)
Net income				50,517				50,517
Dividends on common stock, $0.20, $0.40 and $0.40 per share for the year ended December 31, 2018, 2019 and 2020, respectively				(10,063)				(10,063)
Stock-based compensation expense		2,402						2,402
Vesting of restricted stock, net of shares withheld for employee tax liabilities		(239)						(239)
Vesting of restricted stock, net of shares withheld for employee tax liabilities (in shares)	59,455
Shares repurchased		(3)						(3)
Shares repurchased, Shares	(100)
Other comprehensive income (loss), net of tax						5,361		5,361
Exercise of stock options		(98)			$ 219			121
Exercise of stock options (in shares)					12,926
Ending balance at Dec. 31, 2019	$ 258	346,559		201,080	$ (14,562)	2,386		535,721
Ending balance, shares at Dec. 31, 2019	25,837,048				(857,346)
Net income				26,361				26,361
Dividends on common stock, $0.20, $0.40 and $0.40 per share for the year ended December 31, 2018, 2019 and 2020, respectively				(9,940)				(9,940)
Stock-based compensation expense		1,935						1,935
Vesting of restricted stock, net of shares withheld for employee tax liabilities	$ 1	(199)						(198)
Vesting of restricted stock, net of shares withheld for employee tax liabilities (in shares)	53,582
Exercise of stock options, net of shares withheld for employee tax liabilities		(60)			$ 193			133
Exercise of stock options, net of shares withheld for employee tax liabilities (in shares)					11,358
Shares repurchased	$ (4)	(8,901)						(8,905)
Shares repurchased, Shares	(431,814)
Other comprehensive income (loss), net of tax						4,389		4,389
Ending balance at Dec. 31, 2020	$ 255	$ 339,334		$ 214,456	$ (14,369)	$ 6,775		$ 546,451
Ending balance, shares at Dec. 31, 2020	25,458,816				(845,988)
CECL implementation, net of deferred tax asset			$ (3,045)				$ (3,045)