v3.25.2
Shareholders' Equity (Details) - USD ($)
$ / shares in Units, $ in Thousands
3 Months Ended 6 Months Ended
Jul. 29, 2025
Jun. 30, 2025
Jun. 30, 2024
Jun. 30, 2025
Jun. 30, 2024
Dividends declared (in dollars per share)   $ 0.57 $ 0.55 $ 1.14 $ 1.10
Schedule of Accumulated Other Income (Loss) [Abstract]          
Balance, beginning of period   $ 5,774,378 $ 5,131,635 $ 5,550,957 $ 5,145,419
Net change in unrealized gain (loss)   86,829 (5,943) 260,657 (77,749)
Interest revenue, Investment securities   9,194 12,027 18,638 24,210
Loss (gain) on available-for-sale securities, net   0 (34) 0 45,137
Other comprehensive income, before income taxes   96,023 6,050 279,295 (8,402)
Federal and state income taxes   22,690 1,424 65,265 (2,000)
Other comprehensive income, net of income taxes   73,333 4,626 214,030 (6,402)
Balance, end of period   5,893,356 5,231,970 5,893,356 5,231,970
Accumulated Net Unrealized Gain (Loss) on Available for Sale Securities [Member]          
Schedule of Accumulated Other Income (Loss) [Abstract]          
Balance, beginning of period       (412,348) (473,212)
Net change in unrealized gain (loss)       260,657 (77,749)
Interest revenue, Investment securities       0 0
Loss (gain) on available-for-sale securities, net       0 45,137
Other comprehensive income, before income taxes       260,657 (32,612)
Federal and state income taxes       60,994 (7,695)
Other comprehensive income, net of income taxes       199,663 (24,917)
Balance, end of period   (212,685) (498,129) (212,685) (498,129)
AOCI, Accumulated Gain (Loss), Debt Securities, Investment Securities Transferred from Available-for-sale, Parent          
Schedule of Accumulated Other Income (Loss) [Abstract]          
Balance, beginning of period       (90,692) (125,888)
Net change in unrealized gain (loss)       0 0
Interest revenue, Investment securities       18,638 24,210
Loss (gain) on available-for-sale securities, net       0 0
Other comprehensive income, before income taxes       18,638 24,210
Federal and state income taxes       4,271 5,695
Other comprehensive income, net of income taxes       14,367 18,515
Balance, end of period   (76,325) (107,373) (76,325) (107,373)
Accumulated Other Comprehensive Income (Loss) [Member]          
Schedule of Accumulated Other Income (Loss) [Abstract]          
Balance, beginning of period   (362,343) (610,128) (503,040) (599,100)
Net change in unrealized gain (loss)       260,657 (77,749)
Interest revenue, Investment securities       18,638 24,210
Loss (gain) on available-for-sale securities, net       0 45,137
Other comprehensive income, before income taxes       279,295 (8,402)
Federal and state income taxes       65,265 (2,000)
Other comprehensive income, net of income taxes   73,333 4,626 214,030 (6,402)
Balance, end of period   $ (289,010) $ (605,502) $ (289,010) $ (605,502)
Subsequent Event [Member] | O2025Q3DividendsMember          
Dividends Payable, Date Declared Jul. 29, 2025        
Dividends Payable, Date to be Paid Aug. 27, 2025        
Dividends Payable, Date of Record Aug. 13, 2025        
Schedule of Accumulated Other Income (Loss) [Abstract]          
Dividends Payable, Amount Per Share $ 0.57