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Loans and Allowances for Credit Losses, Activity in Allowance for Credit Losses (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | $ 388,640,000 | $ 236,568,000 |
Provision for loan losses - CECL | (95,202,000) | 222,460,000 |
Loans charged off | (51,351,000) | (79,399,000) | $ (50,977,000)
Recoveries of loans previously charged off | 14,334,000 | 9,011,000 | 10,074,000
Ending Balance - CECL | 256,421,000 | 388,640,000 | 236,568,000
Beginning balance, Incurred Loss Model | 388,640,000 | 210,759,000 | 207,457,000
Provision for loan losses |  |  | 44,205,000
Ending balance, Incurred Loss Model | 256,421,000 | 388,640,000 | 210,759,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 36,921,000 | 25,137,000 |
Provision for off-balance sheet credit risk | (3,944,000) | 11,784,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | 32,977,000 | 36,921,000 | 25,137,000
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 1,585,000 | 1,790,000
Provision for off-balance sheet credit losses |  |  | (205,000)
Ending balance - Incurred loss model |  |  | 1,585,000
Total provision for credit losses | (100,000,000) | 222,592,000 | 44,000,000
Provision Details [Abstract] |  |  |
Change in provision due to changes in reasonable and supportable forecasts, primarily due to COVID-19 pandemic [Line Items] | (90,100,000) |  |
Other changes to provision | (9,000,000) |  |
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 20,071,621,000 | 22,772,827,000 |
Individually measured for impairment, recorded investment | 134,059,000 | 234,693,000 |
Total | 20,205,680,000 | 23,007,520,000 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 250,079,000 | 366,199,000 |
Individually measured for impairment, related allowance | 6,342,000 | 22,441,000 |
Loans and Leases Receivable, Allowance, Total | 256,421,000 | 388,640,000 | 210,759,000
Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | 254,934,000 | 151,868,000 |
Provision for loan losses - CECL | (59,326,000) | 171,800,000 |
Loans charged off | (43,956,000) | (73,370,000) | (43,185,000)
Recoveries of loans previously charged off | 10,404,000 | 4,636,000 | 2,021,000
Ending Balance - CECL | 162,056,000 | 254,934,000 | 151,868,000
Beginning balance, Incurred Loss Model |  | 118,187,000 | 102,226,000
Provision for loan losses |  |  | 57,125,000
Ending balance, Incurred Loss Model |  |  | 118,187,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 14,422,000 | 11,578,000 |
Provision for off-balance sheet credit risk | (610,000) | 2,844,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | 13,812,000 | 14,422,000 | 11,578,000
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 1,434,000 | 1,655,000
Provision for off-balance sheet credit losses |  |  | (221,000)
Ending balance - Incurred loss model |  |  | 1,434,000
Total provision for credit losses |  |  | 56,904,000
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 12,432,361,000 | 12,910,376,000 |
Individually measured for impairment, recorded investment | 74,104,000 | 167,159,000 |
Total | 12,506,465,000 | 13,077,535,000 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 158,063,000 | 235,882,000 |
Individually measured for impairment, related allowance | 3,993,000 | 19,052,000 |
Loans and Leases Receivable, Allowance, Total |  |  | 118,187,000
Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | 86,558,000 | 47,185,000 |
Provision for loan losses - CECL | (26,522,000) | 40,407,000 |
Loans charged off | (2,485,000) | (1,300,000) | (1,161,000)
Recoveries of loans previously charged off | 1,002,000 | 266,000 | 4,986,000
Ending Balance - CECL | 58,553,000 | 86,558,000 | 47,185,000
Beginning balance, Incurred Loss Model |  | 51,805,000 | 60,026,000
Provision for loan losses |  |  | (12,046,000)
Ending balance, Incurred Loss Model |  |  | 51,805,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 20,571,000 | 11,767,000 |
Provision for off-balance sheet credit risk | (3,129,000) | 8,804,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | 17,442,000 | 20,571,000 | 11,767,000
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 107,000 | 52,000
Provision for off-balance sheet credit losses |  |  | 55,000
Ending balance - Incurred loss model |  |  | 107,000
Total provision for credit losses |  |  | (11,991,000)
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 3,817,063,000 | 4,671,292,000 |
Individually measured for impairment, recorded investment | 14,262,000 | 27,246,000 |
Total | 3,831,325,000 | 4,698,538,000 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 56,204,000 | 83,169,000 |
Individually measured for impairment, related allowance | 2,349,000 | 3,389,000 |
Loans and Leases Receivable, Allowance, Total |  |  | 51,805,000
Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | 0 | 0 |
Provision for loan losses - CECL | 0 | 10,253,000 |
Loans charged off | 0 | (4,729,000) |
Recoveries of loans previously charged off | 0 | 4,109,000 |
Ending Balance - CECL | 0 | 0 | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 0 | 0 |
Provision for off-balance sheet credit risk | 0 | 136,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | 0 | 0 | 0
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 276,341,000 | 1,682,310,000 |
Individually measured for impairment, recorded investment | 0 | 0 |
Total | 276,341,000 | 1,682,310,000 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 0 | 0 |
Individually measured for impairment, related allowance | 0 | 0 |
Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | 47,148,000 | 37,515,000 |
Provision for loan losses - CECL | (9,354,000) | 0 |
Loans charged off | (4,910,000) | 0 |
Recoveries of loans previously charged off | 2,928,000 | 0 |
Ending Balance - CECL | 35,812,000 | 47,148,000 | 37,515,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 1,928,000 | 1,792,000 |
Provision for off-balance sheet credit risk | (205,000) | 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | 1,723,000 | 1,928,000 | 1,792,000
Recorded investment [Abstract] |  |  |
Collectively measured for impairment, recorded investment | 3,545,856,000 | 3,508,849,000 |
Individually measured for impairment, recorded investment | 45,693,000 | 40,288,000 |
Total | 3,591,549,000 | 3,549,137,000 |
Related allowance [Abstract] |  |  |
Collectively measured for impairment, related allowance | 35,812,000 | 47,148,000 |
Individually measured for impairment, related allowance | 0 | 0 |
Loans to individuals [Member] | Residential Mortgage [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Loans charged off |  |  | (288,000)
Recoveries of loans previously charged off |  |  | 562,000
Beginning balance, Incurred Loss Model |  | 14,400,000 | 17,964,000
Provision for loan losses |  |  | (3,838,000)
Ending balance, Incurred Loss Model |  |  | 14,400,000
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 44,000 | 52,000
Provision for off-balance sheet credit losses |  |  | (8,000)
Ending balance - Incurred loss model |  |  | 44,000
Total provision for credit losses |  |  | (3,846,000)
Related allowance [Abstract] |  |  |
Loans and Leases Receivable, Allowance, Total |  |  | 14,400,000
Loans to individuals [Member] | Personal [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Loans charged off |  |  | (6,343,000)
Recoveries of loans previously charged off |  |  | 2,505,000
Beginning balance, Incurred Loss Model |  | 9,172,000 | 9,473,000
Provision for loan losses |  |  | 3,537,000
Ending balance, Incurred Loss Model |  |  | 9,172,000
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 0 | 31,000
Provision for off-balance sheet credit losses |  |  | (31,000)
Ending balance - Incurred loss model |  |  | 0
Total provision for credit losses |  |  | 3,506,000
Related allowance [Abstract] |  |  |
Loans and Leases Receivable, Allowance, Total |  |  | 9,172,000
Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL | 0 | 0 |
Provision for loan losses - CECL | 0 | 0 |
Loans charged off | 0 | 0 | 0
Recoveries of loans previously charged off | 0 | 0 | 0
Ending Balance - CECL | 0 | 0 | 0
Beginning balance, Incurred Loss Model |  | 17,195,000 | 17,768,000
Provision for loan losses |  |  | (573,000)
Ending balance, Incurred Loss Model |  |  | 17,195,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL | 0 | 0 |
Provision for off-balance sheet credit risk | 0 | 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL | $ 0 | 0 | 0
Accrual for off-balance sheet credit losses [Roll Forward] |  |  |
Beginning balance - Incurred loss model |  | 0 | 0
Provision for off-balance sheet credit losses |  |  | 0
Ending balance - Incurred loss model |  |  | 0
Total provision for credit losses |  |  | (573,000)
Related allowance [Abstract] |  |  |
Loans and Leases Receivable, Allowance, Total |  |  | 17,195,000
Transition Adjustment [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 25,809,000 |
Ending Balance - CECL |  |  | 25,809,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 23,552,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 23,552,000
Transition Adjustment [Member] | Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 33,681,000 |
Ending Balance - CECL |  |  | 33,681,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 10,144,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 10,144,000
Transition Adjustment [Member] | Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | (4,620,000) |
Ending Balance - CECL |  |  | (4,620,000)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 11,660,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 11,660,000
Transition Adjustment [Member] | Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 13,943,000 |
Ending Balance - CECL |  |  | 13,943,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 1,748,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 1,748,000
Transition Adjustment [Member] | Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 0 |
Ending Balance - CECL |  |  | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 0
Transition Adjustment [Member] | Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | (17,195,000) |
Ending Balance - CECL |  |  | (17,195,000)
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 0
Previously Reported [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 210,759,000 |
Ending Balance - CECL |  |  | 210,759,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 1,585,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 1,585,000
Previously Reported [Member] | Commercial [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 118,187,000 |
Ending Balance - CECL |  |  | 118,187,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 1,434,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 1,434,000
Previously Reported [Member] | Commercial real estate [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 51,805,000 |
Ending Balance - CECL |  |  | 51,805,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 107,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 107,000
Previously Reported [Member] | Paycheck Protection Program |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 23,572,000 |
Ending Balance - CECL |  |  | 23,572,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 44,000 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 44,000
Previously Reported [Member] | Loans to individuals [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 0 |
Ending Balance - CECL |  |  | 0
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | 0
Previously Reported [Member] | Nonspecific Allowance [Member] |  |  |
Allowance for loan losses [Roll Forward] |  |  |
Beginning balance - CECL |  | 17,195,000 |
Ending Balance - CECL |  |  | 17,195,000
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |
Off-Balance Sheet, Credit Loss, Liability, Beginning Balance - CECL |  | $ 0 |
Off-Balance Sheet, Credit Loss, Liability, Ending Balance - CECL |  |  | $ 0

X
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