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Loans and Allowances for Credit Losses, Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2022 | Dec. 31, 2021 | Dec. 31, 2020
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | $ 256,421 | $ 388,640 | $ 236,568
Provision for loan losses | 428 | (95,202) | 222,460
Loans charged off | (28,746) | (51,351) | (79,399)
Recoveries of loans previously charged off | 7,601 | 14,334 | 9,011
Ending balance | 235,704 | 256,421 | 388,640
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 32,977 | 36,921 | 25,137
Provision for off-balance sheet credit risk | 27,942 | (3,944) | 11,784
Ending Balance | 60,919 | 32,977 | 36,921
Total provision for credit losses | 30,000 | (100,000) | 222,592
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 22,435,353 | 20,071,621 |
Individually measured for impairment, recorded investment | 121,797 | 134,059 |
Total | 22,557,150 | 20,205,680 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 230,134 | 250,079 |
Individually measured for impairment, related allowance | 5,570 | 6,342 |
Total | 235,704 | 256,421 |
Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 162,056 | 254,934 | 151,868
Provision for loan losses | (12,782) | (59,326) | 171,800
Loans charged off | (22,382) | (43,956) | (73,370)
Recoveries of loans previously charged off | 4,694 | 10,404 | 4,636
Ending balance | 131,586 | 162,056 | 254,934
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 13,812 | 14,422 | 11,578
Provision for off-balance sheet credit risk | 4,434 | (610) | 2,844
Ending Balance | 18,246 | 13,812 | 14,422
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 14,137,890 | 12,432,361 |
Individually measured for impairment, recorded investment | 60,297 | 74,104 |
Total | 14,198,187 | 12,506,465 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 127,566 | 158,063 |
Individually measured for impairment, related allowance | 4,020 | 3,993 |
Total | 131,586 | 162,056 |
Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 58,553 | 86,558 | 47,185
Provision for loan losses | (813) | (26,522) | 40,407
Loans charged off | (269) | (2,485) | (1,300)
Recoveries of loans previously charged off | 177 | 1,002 | 266
Ending balance | 57,648 | 58,553 | 86,558
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 17,442 | 20,571 | 11,767
Provision for off-balance sheet credit risk | 23,048 | (3,129) | 8,804
Ending Balance | 40,490 | 17,442 | 20,571
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 4,590,207 | 3,817,063 |
Individually measured for impairment, recorded investment | 16,570 | 14,262 |
Total | 4,606,777 | 3,831,325 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 56,098 | 56,204 |
Individually measured for impairment, related allowance | 1,550 | 2,349 |
Total | 57,648 | 58,553 |
Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 0 | 0 | 0
Provision for loan losses | 0 | 0 | 0
Loans charged off | 0 | 0 | 0
Recoveries of loans previously charged off | 0 | 0 | 0
Ending balance | 0 | 0 | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 0 | 0 | 0
Provision for off-balance sheet credit risk | 0 | 0 | 0
Ending Balance | 0 | 0 | 0
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 14,312 | 276,341 |
Individually measured for impairment, recorded investment | 0 | 0 |
Total | 14,312 | 276,341 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 0 | 0 |
Individually measured for impairment, related allowance | 0 | 0 |
Total | 0 | 0 |
Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 35,812 | 47,148 | 37,515
Provision for loan losses | 14,023 | (9,354) | 10,253
Loans charged off | (6,095) | (4,910) | (4,729)
Recoveries of loans previously charged off | 2,730 | 2,928 | 4,109
Ending balance | 46,470 | 35,812 | 47,148
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 1,723 | 1,928 | 1,792
Provision for off-balance sheet credit risk | 460 | (205) | 136
Ending Balance | 2,183 | 1,723 | 1,928
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 3,692,944 | 3,545,856 |
Individually measured for impairment, recorded investment | 44,930 | 45,693 |
Total | 3,737,874 | 3,591,549 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 46,470 | 35,812 |
Individually measured for impairment, related allowance | 0 | 0 |
Total | 46,470 | 35,812 |
Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance | 0 | 0 | 0
Provision for loan losses | 0 | 0 | 0
Loans charged off | 0 | 0 | 0
Recoveries of loans previously charged off | 0 | 0 | 0
Ending balance | 0 | 0 | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance | 0 | 0 | 0
Provision for off-balance sheet credit risk | 0 | 0 | 0
Ending Balance | $ 0 | $ 0 | 0
Transition Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 25,809
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 23,552
Transition Adjustment [Member] | Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 33,681
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 10,144
Transition Adjustment [Member] | Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | (4,620)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 11,660
Transition Adjustment [Member] | Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 0
Transition Adjustment [Member] | Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 13,943
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 1,748
Transition Adjustment [Member] | Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | (17,195)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 0
Previously Reported [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 210,759
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 1,585
Previously Reported [Member] | Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 118,187
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 1,434
Previously Reported [Member] | Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 51,805
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 107
Previously Reported [Member] | Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 0
Previously Reported [Member] | Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 23,572
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | 44
Previously Reported [Member] | Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance |  |  | 17,195
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Beginning Balance |  |  | $ 0

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