Consolidated Statements of Stockholders' Equity (Unaudited) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2023	Jun. 30, 2022	Mar. 31, 2023	Dec. 31, 2022	Mar. 31, 2022	Dec. 31, 2021
Common Stock, Shares, Outstanding	44,130,901		44,130,901			45,641,238
Stockholders' Equity Attributable to Parent	$ 2,854,914	$ 2,871,185	$ 2,854,914	$ 2,871,185	$ 2,830,909	$ 2,886,701	$ 2,965,439	$ 3,018,449
Held In Rabbi Trust At Cost [Member]
Stockholders' Equity Attributable to Parent	$ (3,289)	$ (3,196)	$ (3,289)	$ (3,196)	(3,286)	(3,227)	(3,179)	(3,146)
Retained Earnings
Cash dividends declared per common share (in dollars per share)	$ 0.55	$ 0.51	$ 1.10	$ 1.02
Stockholders' Equity Attributable to Parent	$ 1,009,735	$ 833,857	$ 1,009,735	$ 833,857	971,338	934,442	795,651	766,716
Deferred Compensation, Share-based Payments [Member]
Stockholders' Equity Attributable to Parent	3,289	3,196	3,289	3,196	3,286	3,227	3,179	3,146
AOCI Attributable to Parent [Member]
Stockholders' Equity Attributable to Parent	(152,935)	(109,464)	(152,935)	(109,464)	(135,945)	(163,084)	(78,202)	2,183
Common Stock [Member]
Stockholders' Equity Attributable to Parent	440	459	440	459	439	455	472	472
Additional Paid-in Capital [Member]
Stockholders' Equity Attributable to Parent	$ 1,997,674	$ 2,146,333	$ 1,997,674	$ 2,146,333	$ 1,995,077	$ 2,114,888	$ 2,247,518	$ 2,249,078
Common Class A [Member]
Common Stock, Shares, Outstanding	44,130,901	46,069,761	44,130,901	46,069,761	44,114,827	45,641,238	47,377,125	47,349,778