Consolidated Statements of Stockholders' Equity (Unaudited) - USD ($) $ in Thousands	Total	Common Stock Outstanding	Common Stock	Value of Shares Held in Rabbi Trust at Cost	Deferred Compensation and Other Retirement Benefit Obligations	Additional Paid in Capital		Retained Earnings	Accumulated Other Comprehensive Income/(Loss)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding		45,641,238
Net income	$ 123,891							$ 123,891
Other comprehensive income	10,149								$ 10,149
Cash dividends declared per common share (in dollars per share)								$ 1.10
Common dividend declared	(48,598)							$ (48,598)
Proceeds from exercise of stock options, net of cash paid		1,666
Stock based compensation	3,593					$ 3,593
Proceeds from exercise of stock options, net of cash paid	80		$ 0			80
Restricted stock awards issued, net of awards surrendered		86,559
Restricted stock awards issued, net of awards surrendered	(1,110)		1			(1,111)
Shares issued under direct stock purchase plan		18,471
Shares issued under direct stock purchase plan	1,319		0			1,319
Stock Repurchased During Period, Shares		(1,617,033)
Stock Repurchased During Period, Value	(121,111)		(16)			(121,095)
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits				$ (62)	$ 62
Increase (Decrease) in Deferred Compensation	0
Period End Balance at Jun. 30, 2023	2,854,914		440	(3,289)	3,289	1,997,674		1,009,735	(152,935)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding		44,114,827
Net income	62,644							$ 62,644
Other comprehensive income	(16,990)								(16,990)
Cash dividends declared per common share (in dollars per share)								$ 0.55
Common dividend declared	(24,247)							$ (24,247)
Stock based compensation	1,921					1,921
Restricted stock awards issued, net of awards surrendered		5,484
Restricted stock awards issued, net of awards surrendered	0		1			(1)
Shares issued under direct stock purchase plan		10,590
Shares issued under direct stock purchase plan	677					677
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits				(3)	3
Increase (Decrease) in Deferred Compensation	0
Period End Balance at Jun. 30, 2023	2,854,914		440	(3,289)	3,289	1,997,674		1,009,735	(152,935)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding		44,130,901
Sales and Excise Tax Payable	$ 1,200
Common Stock, Shares, Outstanding	42,873,187	42,873,187
Net income	$ 99,100							$ 99,100
Other comprehensive income	602								602
Cash dividends declared per common share (in dollars per share)								$ 1.14
Common dividend declared	(48,406)							$ (48,406)
Stock based compensation	3,439					3,439
Restricted stock awards issued, net of awards surrendered		105,313
Restricted stock awards issued, net of awards surrendered	(761)		1			(762)
Shares issued under direct stock purchase plan		23,633
Shares issued under direct stock purchase plan	1,321					1,321
Stock Repurchased During Period, Shares		(532,266)
Stock Repurchased During Period, Value	(31,297)		(5)			(31,292)	[1]
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits				(55)	55
Increase (Decrease) in Deferred Compensation	0
Period End Balance at Jun. 30, 2024	2,919,249		423	(3,353)	3,353	1,904,869		1,128,182	(114,225)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding		42,452,457
Net income	51,330							$ 51,330
Other comprehensive income	5,113								5,113
Cash dividends declared per common share (in dollars per share)								$ 0.57
Common dividend declared	(24,209)							$ (24,209)
Stock based compensation	2,139					2,139
Restricted stock awards issued, net of awards surrendered		4,068
Restricted stock awards issued, net of awards surrendered	5		1			4
Shares issued under direct stock purchase plan		13,342
Shares issued under direct stock purchase plan	663					663
Increase (Decrease) in Deferred Compensation and Other Retirement Benefits				50	(50)
Increase (Decrease) in Deferred Compensation	0
Period End Balance at Jun. 30, 2024	$ 2,919,249		$ 423	$ (3,353)	$ 3,353	$ 1,904,869		$ 1,128,182	$ (114,225)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Common Stock, Shares, Outstanding	42,469,867	42,469,867
Sales and Excise Tax Payable	$ 311

[1] Inclusive of $311,000 and $1.2 million impact of excise tax attributable to shares repurchased under the share repurchase program during the six months ended June 30, 2024 and June 30, 2023, respectively