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Loans and Allowances for Credit Losses, Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended |  |
--- | --- | --- | --- | ---
Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Jun. 30, 2019 | Jun. 30, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | $ 315,311 |  | $ 236,568 |  |  |
Beginning balance - Incurred Loss Model |  | $ 205,340 | 210,759 | $ 207,457 |  |
Provision for loan losses - CECL | 134,365 |  | 230,329 |  |  |
Provision for loan losses - incurred |  | 4,918 |  | 12,887 |  |
Loans charged off | (15,570) | (13,227) | (34,487) | (25,002) |  |
Recoveries of loans previously charged off | 1,491 | 5,503 | 3,187 | 7,192 |  |
Ending balance - CECL | 435,597 |  | 435,597 |  |  |
Ending balance - Incurred Loss Model | 435,597 | 202,534 | 435,597 | 202,534 |  |
Provision Details [Abstract] |  |  |  |  |  |
Change in provision due to changes in reasonable and supportable forecasts, primarily due to COVID-19 pandemic | 54,600 |  |  |  |  |
Other changes to provision | 84,200 |  |  |  |  |
Provision change due to changes in impairment, risk grading, and other portfolio changes | 14,400 |  |  |  |  |
Provision change due to risk grading | 55,700 |  |  |  |  |
Provision changes due to net charge-offs | 14,100 |  |  |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 28,514 |  | 25,137 |  |  |
Provision for off-balance sheet credit risk | 4,405 |  | 7,782 |  |  |
Ending balance - CECL | 32,919 |  | 32,919 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 1,821 |  | 1,790 |  |
Provision for off-balance sheet credit losses |  | 82 |  | 113 |  |
Ending balance - Incurred Loss Model |  | 1,903 |  | 1,903 |  |
Total provision for credit losses | 135,321 | 5,000 | 229,092 | 13,000 |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  | $ 23,900,494 | $ 21,570,036
Individually measured for impairment, recorded investment |  |  |  |  | 255,396 | 180,951
Total |  |  |  |  | 24,155,890 | 21,750,987
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  | 411,274 | 176,150
Individually measured for impairment, related allowance |  |  |  |  | 24,323 | 17,414
Total | 435,597 | 202,534 | 210,759 | 202,534 | 435,597 | 210,759
Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 213,438 |  | 151,868 |  |  |
Beginning balance - Incurred Loss Model |  | 103,577 | 118,187 | 102,226 |  |
Provision for loan losses - CECL | 111,153 |  | 188,876 |  |  |
Provision for loan losses - incurred |  | 13,771 |  | 24,879 |  |
Loans charged off | (14,487) | (11,385) | (31,102) | (21,853) |  |
Recoveries of loans previously charged off | 318 | 434 | 780 | 1,145 |  |
Ending balance - CECL | 310,422 |  | 310,422 |  |  |
Ending balance - Incurred Loss Model | 310,422 | 106,397 | 310,422 | 106,397 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 14,040 |  | 11,578 |  |  |
Provision for off-balance sheet credit risk | 542 |  | 3,004 |  |  |
Ending balance - CECL | 14,582 |  | 14,582 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 1,725 |  | 1,655 |  |
Provision for off-balance sheet credit losses |  | 17 |  | 87 |  |
Ending balance - Incurred Loss Model |  | 1,742 |  | 1,742 |  |
Total provision for credit losses |  | 13,788 |  | 24,966 |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  | 13,956,511 | 13,916,234
Individually measured for impairment, recorded investment |  |  |  |  | 201,999 | 115,416
Total |  |  |  |  | 14,158,510 | 14,031,650
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  | 286,639 | 100,773
Individually measured for impairment, related allowance |  |  |  |  | 23,783 | 17,414
Total | 310,422 | 106,397 | 118,187 | 106,397 | 310,422 | 118,187
Commercial real estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 51,461 |  | 47,185 |  |  |
Beginning balance - Incurred Loss Model |  | 58,134 | 51,805 | 60,026 |  |
Provision for loan losses - CECL | 17,221 |  | 22,336 |  |  |
Provision for loan losses - incurred |  | (8,173) |  | (10,177) |  |
Loans charged off | (1) | (118) | (887) | (118) |  |
Recoveries of loans previously charged off | 75 | 4,345 | 122 | 4,457 |  |
Ending balance - CECL | 68,756 |  | 68,756 |  |  |
Ending balance - Incurred Loss Model | 68,756 | 54,188 | 68,756 | 54,188 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 12,575 |  | 11,767 |  |  |
Provision for off-balance sheet credit risk | 3,844 |  | 4,652 |  |  |
Ending balance - CECL | 16,419 |  | 16,419 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 48 |  | 52 |  |
Provision for off-balance sheet credit losses |  | 68 |  | 64 |  |
Ending balance - Incurred Loss Model |  | 116 |  | 116 |  |
Total provision for credit losses |  | (8,105) |  | (10,113) |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  | 4,540,188 | 4,406,157
Individually measured for impairment, recorded investment |  |  |  |  | 13,956 | 27,626
Total |  |  |  |  | 4,554,144 | 4,433,783
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  | 68,216 | 51,805
Individually measured for impairment, related allowance |  |  |  |  | 540 | 0
Total | 68,756 | 54,188 | 51,805 | 54,188 | 68,756 | 51,805
Paycheck Protection Program |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 0 |  | 0 |  |  |
Provision for loan losses - CECL | 0 |  | 0 |  |  |
Loans charged off | 0 |  | 0 |  |  |
Recoveries of loans previously charged off | 0 |  | 0 |  |  |
Ending balance - CECL | 0 |  | 0 |  |  |
Ending balance - Incurred Loss Model | 0 |  | 0 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 0 |  | 0 |  |  |
Provision for off-balance sheet credit risk | 0 |  | 0 |  |  |
Ending balance - CECL | 0 |  | 0 |  |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  | 2,081,428 |
Individually measured for impairment, recorded investment |  |  |  |  | 0 |
Total |  |  |  |  | 2,081,428 |
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  | 0 |
Individually measured for impairment, related allowance |  |  |  |  | 0 |
Total | 0 |  | 0 |  | 0 |
Loans to individuals [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 50,412 |  | 37,515 |  |  |
Provision for loan losses - CECL | 5,991 |  | 19,117 |  |  |
Loans charged off | (1,082) |  | (2,498) |  |  |
Recoveries of loans previously charged off | 1,098 |  | 2,285 |  |  |
Ending balance - CECL | 56,419 |  | 56,419 |  |  |
Ending balance - Incurred Loss Model | 56,419 |  | 56,419 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 1,899 |  | 1,792 |  |  |
Provision for off-balance sheet credit risk | 19 |  | 126 |  |  |
Ending balance - CECL | 1,918 |  | 1,918 |  |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  | 3,322,367 |
Individually measured for impairment, recorded investment |  |  |  |  | 39,441 |
Total |  |  |  |  | 3,361,808 | 2,084,172
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  | 56,419 |
Individually measured for impairment, related allowance |  |  |  |  | 0 |
Total | 56,419 |  | 56,419 |  | 56,419 |
Loans to individuals [Member] | Residential mortgage [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 15,668 | 14,400 | 17,964 |  |
Provision for loan losses - incurred |  | 1 |  | (2,407) |  |
Loans charged off |  | (94) |  | (136) |  |
Recoveries of loans previously charged off |  | 149 |  | 303 |  |
Ending balance - Incurred Loss Model |  | 15,724 |  | 15,724 |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 47 |  | 52 |  |
Provision for off-balance sheet credit losses |  | (3) |  | (8) |  |
Ending balance - Incurred Loss Model |  | 44 |  | 44 |  |
Total provision for credit losses |  | (2) |  | (2,415) |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  |  | 2,046,550
Individually measured for impairment, recorded investment |  |  |  |  |  | 37,622
Total |  |  |  |  | 1,813,442 | 2,084,172
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  |  | 14,400
Individually measured for impairment, related allowance |  |  |  |  |  | 0
Total |  | 15,724 | 14,400 | 17,964 |  | 14,400
Loans to individuals [Member] | Personal [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 8,783 | 9,172 | 9,473 |  |
Provision for loan losses - incurred |  | 1,660 |  | 1,523 |  |
Loans charged off |  | (1,630) |  | (2,895) |  |
Recoveries of loans previously charged off |  | 575 |  | 1,287 |  |
Ending balance - Incurred Loss Model |  | 9,388 |  | 9,388 |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 1 |  | 31 |  |
Provision for off-balance sheet credit losses |  | 0 |  | (30) |  |
Ending balance - Incurred Loss Model |  | 1 |  | 1 |  |
Total provision for credit losses |  | 1,660 |  | 1,493 |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  |  | 1,201,095
Individually measured for impairment, recorded investment |  |  |  |  |  | 287
Total |  |  |  |  | $ 1,226,097 | 1,201,382
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  |  | 9,172
Individually measured for impairment, related allowance |  |  |  |  |  | 0
Total |  | 9,388 | 9,172 | 9,473 |  | 9,172
Specific Allowance [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  |  | 193,564 |  |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  |  | 21,570,036
Individually measured for impairment, recorded investment |  |  |  |  |  | 180,951
Total |  |  |  |  |  | 21,750,987
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  |  | 176,150
Individually measured for impairment, related allowance |  |  |  |  |  | 17,414
Total |  |  | 193,564 |  |  | 193,564
Nonspecific Allowance [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 0 |  | 0 |  |  |
Beginning balance - Incurred Loss Model |  | 19,178 | 17,195 | 17,768 |  |
Provision for loan losses - CECL | 0 |  | 0 |  |  |
Provision for loan losses - incurred |  | (2,341) |  | (931) |  |
Loans charged off | 0 | 0 | 0 | 0 |  |
Recoveries of loans previously charged off | 0 | 0 | 0 | 0 |  |
Ending balance - CECL | 0 |  | 0 |  |  |
Ending balance - Incurred Loss Model |  | 16,837 |  | 16,837 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL | 0 |  | 0 |  |  |
Provision for off-balance sheet credit risk | 0 |  | 0 |  |  |
Ending balance - CECL | $ 0 |  | 0 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |  |  |
Beginning balance - Incurred Loss Model |  | 0 |  | 0 |  |
Provision for off-balance sheet credit losses |  | 0 |  | 0 |  |
Ending balance - Incurred Loss Model |  | 0 |  | 0 |  |
Total provision for credit losses |  | (2,341) |  | (931) |  |
Recorded investment [Abstract] |  |  |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  |  |  | 0
Individually measured for impairment, recorded investment |  |  |  |  |  | 0
Total |  |  |  |  |  | 0
Related allowance [Abstract] |  |  |  |  |  |
Collectively measured for impairment, related allowance |  |  |  |  |  | 0
Individually measured for impairment, related allowance |  |  |  |  |  | 0
Total |  | $ 16,837 | 17,195 | $ 17,768 |  | $ 17,195
Previously Reported [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 210,759 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 1,585 |  |  |
Previously Reported [Member] | Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 118,187 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 1,434 |  |  |
Previously Reported [Member] | Commercial real estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 51,805 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 107 |  |  |
Previously Reported [Member] | Paycheck Protection Program |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 0 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 0 |  |  |
Previously Reported [Member] | Loans to individuals [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 23,572 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 44 |  |  |
Previously Reported [Member] | Nonspecific Allowance [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 17,195 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 0 |  |  |
Restatement Adjustment [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 25,809 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 23,552 |  |  |
Restatement Adjustment [Member] | Commercial [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 33,681 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 10,144 |  |  |
Restatement Adjustment [Member] | Commercial real estate [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | (4,620) |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 11,660 |  |  |
Restatement Adjustment [Member] | Paycheck Protection Program |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 0 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 0 |  |  |
Restatement Adjustment [Member] | Loans to individuals [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 13,943 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | 1,748 |  |  |
Restatement Adjustment [Member] | Nonspecific Allowance [Member] |  |  |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | (17,195) |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |  |  |
Beginning balance - CECL |  |  | $ 0 |  |  |

X
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