Consolidated Statements of Shareholders' Equity (unaudited) - USD ($) $ in Thousands	Total	Common Shares	Additional Paid-In Capital	Retained Earnings	Accumulated Other Comprehensive Income (Loss)
Beginning balance, shares (in shares) at Dec. 31, 2020		41,469,879
Beginning balance at Dec. 31, 2020	$ 870,966	$ 207,349	$ 414,246	$ 257,878	$ (8,507)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)		68,830
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes	(1,488)	$ 345	(1,833)
Stock Issued Under Dividend Reinvestment and Stock Purchase Plans, net of expenses and repurchased shares	(67)		(67)
Net Income	72,398			72,398
Other Comprehensive Income (Loss)	216				216
Stock Compensation Expense	5,524		5,524
Common Dividends	(32,426)			(32,426)
Ending balance, shares (in shares) at Jun. 30, 2021		41,538,709
Ending balance at Jun. 30, 2021	915,123	$ 207,694	417,870	297,850	(8,291)
Beginning balance, shares (in shares) at Mar. 31, 2021		41,510,455
Beginning balance at Mar. 31, 2021	887,866	$ 207,552	416,707	271,999	(8,392)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)		28,254
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes	19	$ 142	(123)
Stock Issued Under Dividend Reinvestment and Stock Purchase Plans, net of expenses and repurchased shares	(41)		(41)
Net Income	42,069			42,069
Other Comprehensive Income (Loss)	101				101
Stock Compensation Expense	1,327		1,327
Common Dividends	(16,218)			(16,218)
Ending balance, shares (in shares) at Jun. 30, 2021		41,538,709
Ending balance at Jun. 30, 2021	$ 915,123	$ 207,694	417,870	297,850	(8,291)
Beginning balance, shares (in shares) at Dec. 31, 2021	41,551,524	41,551,524
Beginning balance at Dec. 31, 2021	$ 990,777	$ 207,758	419,760	369,783	(6,524)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)		79,275
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes	(2,924)	$ 396	(3,320)
Net Income	157,940			157,940
Other Comprehensive Income (Loss)	(389)				(389)
Stock Compensation Expense	5,511		5,511
Common Dividends	$ (34,372)			(34,372)
Ending balance, shares (in shares) at Jun. 30, 2022	41,630,799	41,630,799
Ending balance at Jun. 30, 2022	$ 1,116,543	$ 208,154	421,951	493,351	(6,913)
Beginning balance, shares (in shares) at Mar. 31, 2022		41,605,884
Beginning balance at Mar. 31, 2022	1,047,138	$ 208,029	421,449	424,605	(6,945)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes (in shares)		24,915
Stock Issued Under Share-Based Compensation Plans, net of shares withheld for employee taxes	20	$ 125	(105)
Net Income	85,937			85,937
Other Comprehensive Income (Loss)	32				32
Stock Compensation Expense	607		607
Common Dividends	$ (17,191)			(17,191)
Ending balance, shares (in shares) at Jun. 30, 2022	41,630,799	41,630,799
Ending balance at Jun. 30, 2022	$ 1,116,543	$ 208,154	$ 421,951	$ 493,351	$ (6,913)