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Loans and Allowances for Credit Losses, Activity in Allowance for Credit Losses (Details) - USD ($) $ in Thousands | 3 Months Ended |  |
--- | --- | --- | ---
Mar. 31, 2020 | Mar. 31, 2019 | Mar. 31, 2020 | Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - CECL | $ 236,568 |  |  |
Beginning balance - Incurred Loss Model | 210,759 | $ 207,457 |  |
Provision for loan losses - CECL | 95,964 |  |  |
Provision for loan losses - incurred |  | 7,969 |  |
Loans charged off | (18,917) | (11,775) |  |
Recoveries of loans previously charged off | 1,696 | 1,689 |  |
Ending balance - CECL | 315,311 |  |  |
Ending balance - Incurred Loss Model | 315,311 | 205,340 |  |
Provision Details [Abstract] |  |  |  |
Change in provision due to changes in reasonable and supportable forecasts, primarily due to COVID-19 pandemic | 66,200 |  |  |
Other changes to provision | 33,100 |  |  |
Provision change due to loan growth | 7,500 |  |  |
Provision change due to changes in impairment, risk grading, and other portfolio changes | 8,400 |  |  |
Provision changes due to net charge-offs | 17,200 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |
Beginning balance - CECL | 25,137 |  |  |
Provision for off-balance sheet credit risk | 3,377 |  |  |
Ending balance - CECL | 28,514 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 1,790 |  |
Provision for off-balance sheet credit losses |  | 31 |  |
Ending balance - Incurred Loss Model |  | 1,821 |  |
Total provision for credit losses | 93,771 | 8,000 |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  | $ 22,300,798 | $ 21,570,036
Individually measured for impairment, recorded investment |  |  | 163,172 | 180,951
Total |  |  | 22,463,970 | 21,750,987
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  | 305,427 | 176,150
Individually measured for impairment, related allowance |  |  | 9,884 | 17,414
Total | 210,759 | 205,340 | 315,311 | 210,759
Commercial [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - CECL | 151,868 |  |  |
Beginning balance - Incurred Loss Model | 118,187 | 102,226 |  |
Provision for loan losses - CECL | 77,723 |  |  |
Provision for loan losses - incurred |  | 11,108 |  |
Loans charged off | (16,615) | (10,468) |  |
Recoveries of loans previously charged off | 462 | 711 |  |
Ending balance - CECL | 213,438 |  |  |
Ending balance - Incurred Loss Model | 213,438 | 103,577 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |
Beginning balance - CECL | 11,578 |  |  |
Provision for off-balance sheet credit risk | 2,462 |  |  |
Ending balance - CECL | 14,040 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 1,655 |  |
Provision for off-balance sheet credit losses |  | 70 |  |
Ending balance - Incurred Loss Model |  | 1,725 |  |
Total provision for credit losses |  | 11,178 |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  | 14,677,351 | 13,916,234
Individually measured for impairment, recorded investment |  |  | 118,624 | 115,416
Total |  |  | 14,795,975 | 14,031,650
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  | 203,554 | 100,773
Individually measured for impairment, related allowance |  |  | 9,884 | 17,414
Total | 118,187 | 103,577 | 213,438 | 118,187
Commercial real estate [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - CECL | 47,185 |  |  |
Beginning balance - Incurred Loss Model | 51,805 | 60,026 |  |
Provision for loan losses - CECL | 5,115 |  |  |
Provision for loan losses - incurred |  | (2,004) |  |
Loans charged off | (886) | 0 |  |
Recoveries of loans previously charged off | 47 | 112 |  |
Ending balance - CECL | 51,461 |  |  |
Ending balance - Incurred Loss Model | 51,461 | 58,134 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |
Beginning balance - CECL | 11,767 |  |  |
Provision for off-balance sheet credit risk | 808 |  |  |
Ending balance - CECL | 12,575 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 52 |  |
Provision for off-balance sheet credit losses |  | (4) |  |
Ending balance - Incurred Loss Model |  | 48 |  |
Total provision for credit losses |  | (2,008) |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  | 4,441,540 | 4,406,157
Individually measured for impairment, recorded investment |  |  | 8,545 | 27,626
Total |  |  | 4,450,085 | 4,433,783
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  | 51,461 | 51,805
Individually measured for impairment, related allowance |  |  | 0 | 0
Total | 51,805 | 58,134 | 51,461 | 51,805
Loans to individuals [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - CECL | 37,515 |  |  |
Provision for loan losses - CECL | 13,126 |  |  |
Loans charged off | (1,416) |  |  |
Recoveries of loans previously charged off | 1,187 |  |  |
Ending balance - CECL | 50,412 |  |  |
Ending balance - Incurred Loss Model | 50,412 |  |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |
Beginning balance - CECL | 1,792 |  |  |
Provision for off-balance sheet credit risk | 107 |  |  |
Ending balance - CECL | 1,899 |  |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  | 3,181,907 |
Individually measured for impairment, recorded investment |  |  | 36,003 |
Total |  |  | 3,217,910 | 2,084,172
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  | 50,412 |
Individually measured for impairment, related allowance |  |  | 0 |
Total | 50,412 |  | 50,412 |
Loans to individuals [Member] | Residential mortgage [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model | 14,400 | 17,964 |  |
Provision for loan losses - incurred |  | (2,408) |  |
Loans charged off |  | (42) |  |
Recoveries of loans previously charged off |  | 154 |  |
Ending balance - Incurred Loss Model |  | 15,668 |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 52 |  |
Provision for off-balance sheet credit losses |  | (5) |  |
Ending balance - Incurred Loss Model |  | 47 |  |
Total provision for credit losses |  | (2,413) |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  | 2,046,550
Individually measured for impairment, recorded investment |  |  |  | 37,622
Total |  |  | 1,844,555 | 2,084,172
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  |  | 14,400
Individually measured for impairment, related allowance |  |  |  | 0
Total | 14,400 | 15,668 |  | 14,400
Loans to individuals [Member] | Personal [Member] |  |  |  |
Financing Receivable, Allowance for Credit Loss [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model | 9,172 | 9,473 |  |
Provision for loan losses - incurred |  | (137) |  |
Loans charged off |  | (1,265) |  |
Recoveries of loans previously charged off |  | 712 |  |
Ending balance - Incurred Loss Model |  | 8,783 |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 31 |  |
Provision for off-balance sheet credit losses |  | (30) |  |
Ending balance - Incurred Loss Model |  | 1 |  |
Total provision for credit losses |  | (167) |  |
Recorded investment [Abstract] |  |  |  |
Collectively measured for impairment, recorded investment |  |  |  | 1,201,095
Individually measured for impairment, recorded investment |  |  |  | 287
Total |  |  | $ 1,175,466 | 1,201,382
Related allowance [Abstract] |  |  |  |
Collectively measured for impairment, related allowance |  |  |  | 9,172
Individually measured for impairment, related allowance |  |  |  | 0
Total | 9,172 | 8,783 |  | 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 |  |  |
Beginning balance - Incurred Loss Model | 17,195 | 17,768 |  |
Provision for loan losses - CECL | 0 |  |  |
Provision for loan losses - incurred |  | 1,410 |  |
Loans charged off | 0 | 0 |  |
Recoveries of loans previously charged off | 0 | 0 |  |
Ending balance - CECL | 0 |  |  |
Ending balance - Incurred Loss Model |  | 19,178 |  |
Off-Balance Sheet, Credit Loss, Liability [Roll Forward] |  |  |  |
Beginning balance - CECL | 0 |  |  |
Provision for off-balance sheet credit risk | 0 |  |  |
Ending balance - CECL | 0 |  |  |
Allowance for off-balance sheet credit losses [Roll Forward] |  |  |  |
Beginning balance - Incurred Loss Model |  | 0 |  |
Provision for off-balance sheet credit losses |  | 0 |  |
Ending balance - Incurred Loss Model |  | 0 |  |
Total provision for credit losses |  | 1,410 |  |
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 | 17,195 | $ 19,178 |  | $ 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] | 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] | 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 |  |  |

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