Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Reconciliation of information used in computing basic and diluted earnings per share [Abstract]
Net earnings	$ 632,221	$ 228,574
Basic earnings per common share:
Net earnings (in dollars per share)	$ 4.55	$ 1.64
Weighted average shares outstanding (in shares)	139,051	139,757
Diluted earnings per common share:
Net earnings (in dollars per share)	$ 4.52	$ 1.63
Weighted average shares outstanding (in shares)	139,869	140,616
Reconciliation Of Share Amounts Used In Computing Earnings Per Share [Abstract]
Weighted average shares outstanding - basic (in shares)	139,051	139,757
Dilutive effect of assumed exercise of SARs and vesting of performance shares and RSUs (in shares)	818	859
Weighted average shares outstanding - Diluted (in shares)	139,869	140,616
Antidilutive securities excluded from computation of earnings per share	107	88