Condensed Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands		Total		Common Stock [Member]		Additional Paid-In Capital [Member]		Retained Earnings [Member]	Accumulated Other Comprehensive Loss [Member]	Deferred Compensation [Member]	Treasury Stock [Member]
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares Held In Trust For Deferred Compensation Plan		105,087
Common Stock, Dividends, Per Share, Declared		$ 0.4400
Beginning Balances (shares) at Dec. 31, 2020	[1],[2]			17,461,841
Beginning Balances at Dec. 31, 2020		$ 697,085	[1],[2]	$ 8,499	[1],[2]	$ 348,482		$ 342,969	$ (2,865)	$ 5,679	$ (5,679)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		34,466						34,466
Other comprehensive income (loss)		227							227
Other Comprehensive Income (Loss), Net of Tax		227
Dividend declared		(7,812)						(7,812)
Retirement savings plan and dividend reinvestment plan (shares)				20,511
Dividend reinvestment plan		2,214		$ 10		2,204
Share-based compensation (shares)	[3],[4]			39,141
Share-based compensation and tax benefit		208		$ 19	[3],[4]	189	[3],[4]
Treasury stock activities		0								1,313	(1,313)
Ending Balances (shares) at Mar. 31, 2021	[1]			17,521,493
Ending Balances at Mar. 31, 2021		$ 726,388	[1]	$ 8,528	[1]	350,875		369,623	(2,638)	6,992	(6,992)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		14,020
Shares Held In Trust For Deferred Compensation Plan		116,751
Preferred Stock, Shares Authorized		2,000,000
Preferred Stock, Par or Stated Value Per Share		$ 0.01
Shares Held In Trust For Deferred Compensation Plan		116,238
Common Stock, Dividends, Per Share, Declared		$ 0.4800
Beginning Balances (shares) at Dec. 31, 2021	[1],[2]			17,655,410
Beginning Balances at Dec. 31, 2021		$ 774,130		$ 8,593	[1],[2]	371,162		393,072	1,303	7,240	(7,240)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net Income		36,933						36,933
Other comprehensive income (loss)		547							547
Other Comprehensive Income (Loss), Net of Tax		547
Dividend declared		(8,661)						(8,661)
Retirement savings plan and dividend reinvestment plan (shares)				24,960
Dividend reinvestment plan		3,422		$ 12		3,410
Share-based compensation (shares)	[3],[4]			39,018
Share-based compensation and tax benefit	[3],[4]	(859)		$ 19		(878)
Treasury stock activities								0		(763)	763
Ending Balances (shares) at Mar. 31, 2022	[1]			17,719,388
Ending Balances at Mar. 31, 2022		$ 805,512	[1]	$ 8,624	[1]	$ 373,694		$ 421,344	$ 1,850	$ 6,477	$ (6,477)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based Payment Arrangement, Shares Withheld for Tax Withholding Obligation		21,832
Preferred Stock, Shares Authorized		2,000,000
Preferred Stock, Par or Stated Value Per Share		$ 0.01
Shares Held In Trust For Deferred Compensation Plan		107,518

[1] 2,000,000 shares of preferred stock at $0.01 par value have been authorized. No shares have been issued or are outstanding; accordingly, no information has been included in the statements of stockholders’ equity.    

[2] Includes 107,518, 116,238, 116,751, and 105,087 shares at March 31, 2022, December 31, 2021, March 31, 2021 and December 31, 2020, respectively, held in a Rabbi Trust related to our Non-Qualified Deferred Compensation Plan.

[3] Includes amounts for shares issued for directors’ compensation.

[4] The shares issued under the SICP are net of shares withheld for employee taxes. For the three months ended March 31, 2022 and 2021, we withheld 21,832 and 14,020 shares, respectively, for employee taxes.(5)Includes the Retirement Savings Plan, DRIP and ATM equity issuances.