Earnings per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022
Basic earnings per share [Abstract]
Net income	$ 762,994	$ 712,949	$ 865,349
Weighted average common shares outstanding - basic (in shares)	261,684	283,605	305,847
Basic earnings per share (in dollars per share)	$ 2.92	$ 2.51	$ 2.83
Diluted earnings per share [Abstract]
Net income	$ 762,994	$ 712,949	$ 865,349
9% Debentures	0	1,026	3,228
Diluted income available to common shareholders	$ 762,994	$ 713,975	$ 868,577
Weighted-average shares - basic (in shares)	261,684	283,605	305,847
Effect of dilutive securities [Abstract]
Unvested restricted stock units	2,311	2,427	1,917
9% Debentures	0	1,123	3,465
Weighted-average shares - diluted (in shares)	263,995	287,155	311,229
Diluted income per share (in dollars per share)	$ 2.89	$ 2.49	$ 2.79
Federal statutory income tax rate (in hundredths)	21.00%	21.00%	21.00%
9% Convertible Junior Subordinated Debentures due 2063
Effect of dilutive securities [Abstract]
Stated interest rate (in hundredths)		9.00%	9.00%