CONSOLIDATED STATEMENTS OF STOCKHOLDERS' EQUITY - USD ($) $ in Thousands	Common Stock	Additional Paid-in Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)	Treasury Stock	Stockholders' Equity, Total
Equity Balance at Dec. 31, 2019	$ 143	$ 33,510	$ 537,167	$ 32,246		$ 603,066
Net Income			14,868			14,868
Stock issued under Stock Option Plan		448			$ 87	535
Common dividends declared			(19,054)			(19,054)
Other comprehensive gain				22,965		22,965
Purchase of the Company's common stock					(8,148)	(8,148)
Reclassification of treasury stock per Maryland law	(2)		(8,059)		8,061
Equity Balance at Mar. 31, 2020	141	33,958	524,922	55,211		614,232
Equity Balance at Dec. 31, 2020	138	35,004	541,448	53,151		629,741
Net Income			18,868			18,868
Stock issued under Stock Option Plan		657			263	920
Common dividends declared			(4,656)			(4,656)
Other comprehensive gain				(15,461)		(15,461)
Purchase of the Company's common stock					(3,780)	(3,780)
Reclassification of treasury stock per Maryland law	(1)		(3,516)		$ 3,517
Equity Balance (CECL adoption) at Mar. 31, 2021			(14,175)			(14,175)
Equity Balance at Mar. 31, 2021	$ 137	$ 35,661	$ 537,969	$ 37,690		$ 611,457