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Allowance for Credit Losses (Summary of Allowance for Credit Losses) (Details) - USD ($) | 12 Months Ended |  |
--- | --- | --- | ---
Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2020 | Jan. 01, 2020
Receivables [Abstract] |  |  |  |  |
Financing receivable, allowance for credit loss, expected, COVID-19 |  |  |  | $ 0 |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | $ 225,141,000 | $ 223,712,000 | $ 221,893,000 |  |
Provisions | 58,352,000 |  | 28,467,000 |  |
Initial PCD allowance | 1,193,000 |  |  |  |
Charge-offs | (45,105,000) |  | (39,671,000) |  |
Recoveries | 22,657,000 |  | 13,023,000 |  |
Ending balance | 224,314,000 | 225,141,000 | 223,712,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 224,314,000 | 223,712,000 | 223,712,000 | 224,314,000 |
Financing Receivable, Allowance For Credit Loss, Decrease, COVID-19 | $ 36,100,000 |  |  |  |
Allowance for credit loss, forecast period | 2 years |  |  |  |
Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | $ 217,605,000 |  |  |  |
Ending balance |  | 217,605,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 217,605,000 | 217,605,000 |  |  |
PCD Loans |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 7,536,000 | 9,144,000 | 10,026,000 |  |
Provisions | (7,202,000) | (1,608,000) | (765,000) |  |
Initial PCD allowance | 1,193,000 |  |  |  |
Charge-offs | (3,300,000) | 0 | (117,000) |  |
Recoveries | 6,759,000 | 0 | 0 |  |
Ending balance | 23,987,000 | 7,536,000 | 9,144,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 7,536,000 | 7,536,000 | 9,144,000 | 23,987,000 |
Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | (37,924,000) |  |  |  |
Ending balance |  | (37,924,000) |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | (37,924,000) | (37,924,000) |  |  | $ (37,900,000)
Cumulative Effect, Period of Adoption, Adjustment | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss |  |  |  |  | (56,900,000)
Cumulative Effect, Period of Adoption, Adjustment | PCD Loans |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 19,001,000 |  |  |  |
Ending balance |  | 19,001,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 19,001,000 | 19,001,000 |  |  | $ 19,000,000.0
Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 187,217,000 |  |  |  |
Ending balance |  | 187,217,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 187,217,000 | 187,217,000 |  |  |
Cumulative Effect, Period of Adoption, Adjusted Balance | PCD Loans |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 26,537,000 |  |  |  |
Ending balance |  | 26,537,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 26,537,000 | 26,537,000 |  |  |
Commercial | Construction and land development |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 33,213,000 | 35,270,000 | 24,470,000 |  |
Provisions | 4,301,000 |  | 10,533,000 |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (138,000) |  | (44,000) |  |
Recoveries | 431,000 |  | 311,000 |  |
Ending balance | 6,746,000 | 33,213,000 | 35,270,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 6,746,000 | 35,270,000 | 35,270,000 | 6,746,000 |
Commercial | Construction and land development | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 33,213,000 |  |  |  |
Ending balance |  | 33,213,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 33,213,000 | 33,213,000 |  |  |
Commercial | Construction and land development | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | (31,061,000) |  |  |  |
Ending balance |  | (31,061,000) |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | (31,061,000) | (31,061,000) |  |  |
Commercial | Construction and land development | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,152,000 |  |  |  |
Ending balance |  | 2,152,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,152,000 | 2,152,000 |  |  |
Commercial | Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance |  | 43,451,000 | 45,005,000 |  |
Provisions |  |  | (1,490,000) |  |
Charge-offs |  |  | (1,140,000) |  |
Recoveries |  |  | 1,076,000 |  |
Ending balance |  |  | 43,451,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss |  | 43,451,000 | 43,451,000 |  |
Commercial | Mortgage | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 45,335,000 |  |  |  |
Ending balance |  | 45,335,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 45,335,000 | 45,335,000 |  |  |
Commercial | Other commercial real estate |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance |  | 2,481,000 | 4,571,000 |  |
Provisions |  |  | (2,171,000) |  |
Charge-offs |  |  | (69,000) |  |
Recoveries |  |  | 150,000 |  |
Ending balance |  |  | 2,481,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss |  | 2,481,000 | 2,481,000 |  |
Commercial | Other commercial real estate | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,211,000 |  |  |  |
Ending balance |  | 2,211,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,211,000 | 2,211,000 |  |  |
Commercial | Commercial and industrial |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 61,610,000 | 55,620,000 | 59,824,000 |  |
Provisions | 13,816,000 |  | 2,511,000 |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (14,904,000) |  | (10,211,000) |  |
Recoveries | 4,894,000 |  | 3,496,000 |  |
Ending balance | 27,779,000 | 61,610,000 | 55,620,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 27,779,000 | 55,620,000 | 55,620,000 | 27,779,000 |
Commercial | Commercial and industrial | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 59,374,000 |  |  |  |
Ending balance |  | 59,374,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 59,374,000 | 59,374,000 |  |  |
Commercial | Commercial and industrial | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | (37,637,000) |  |  |  |
Ending balance |  | (37,637,000) |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | (37,637,000) | (37,637,000) |  |  |
Commercial | Commercial and industrial | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 23,973,000 |  |  |  |
Ending balance |  | 23,973,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 23,973,000 | 23,973,000 |  |  |
Commercial | Other |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance |  | 2,221,000 | 4,689,000 |  |
Provisions |  |  | (2,827,000) |  |
Charge-offs |  |  | (130,000) |  |
Recoveries |  |  | 489,000 |  |
Ending balance |  |  | 2,221,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss |  | 2,221,000 | 2,221,000 |  |
Commercial | Other | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,236,000 |  |  |  |
Ending balance |  | 2,236,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,236,000 | 2,236,000 |  |  |
Commercial | Mortgage Receivable, Owner Occupied |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 36,444,000 |  |  |  |
Provisions | 6,729,000 |  |  |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (593,000) |  |  |  |
Recoveries | 401,000 |  |  |  |
Ending balance | 23,665,000 | 36,444,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 23,665,000 | 36,444,000 |  | 23,665,000 |
Commercial | Mortgage Receivable, Owner Occupied | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | (19,316,000) |  |  |  |
Ending balance |  | (19,316,000) |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | (19,316,000) | (19,316,000) |  |  |
Commercial | Mortgage Receivable, Owner Occupied | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 17,128,000 |  |  |  |
Ending balance |  | 17,128,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 17,128,000 | 17,128,000 |  |  |
Commercial | Mortgage Receivable, Non-Owner Occupied |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 11,102,000 |  |  |  |
Provisions | 12,917,000 |  |  |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (1,951,000) |  |  |  |
Recoveries | 124,000 |  |  |  |
Ending balance | 22,652,000 | 11,102,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 22,652,000 | 11,102,000 |  | 22,652,000 |
Commercial | Mortgage Receivable, Non-Owner Occupied | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 460,000 |  |  |  |
Ending balance |  | 460,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 460,000 | 460,000 |  |  |
Commercial | Mortgage Receivable, Non-Owner Occupied | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 11,562,000 |  |  |  |
Ending balance |  | 11,562,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 11,562,000 | 11,562,000 |  |  |
Consumer Portfolio Segment | Construction and land development |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,709,000 | 2,350,000 | 3,962,000 |  |
Provisions | 266,000 |  | (1,520,000) |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (70,000) |  | (219,000) |  |
Recoveries | 117,000 |  | 127,000 |  |
Ending balance | 1,731,000 | 2,709,000 | 2,350,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 1,731,000 | 2,350,000 | 2,350,000 | 1,731,000 |
Consumer Portfolio Segment | Construction and land development | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,709,000 |  |  |  |
Ending balance |  | 2,709,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,709,000 | 2,709,000 |  |  |
Consumer Portfolio Segment | Construction and land development | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | (1,291,000) |  |  |  |
Ending balance |  | (1,291,000) |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | (1,291,000) | (1,291,000) |  |  |
Consumer Portfolio Segment | Construction and land development | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 1,418,000 |  |  |  |
Ending balance |  | 1,418,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 1,418,000 | 1,418,000 |  |  |
Consumer Portfolio Segment | Mortgage | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 18,232,000 |  |  |  |
Ending balance |  | 18,232,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 18,232,000 | 18,232,000 |  |  |
Consumer Portfolio Segment | Consumer |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance |  | 35,841,000 | 31,204,000 |  |
Provisions |  |  | 22,187,000 |  |
Charge-offs |  |  | (22,817,000) |  |
Recoveries |  |  | 5,267,000 |  |
Ending balance |  |  | 35,841,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss |  | 35,841,000 | 35,841,000 |  |
Consumer Portfolio Segment | Consumer | Financial Asset Acquired and No Credit Deterioration |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 34,593,000 |  |  |  |
Ending balance |  | 34,593,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 34,593,000 | 34,593,000 |  |  |
Consumer Portfolio Segment | Residential Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 18,232,000 | 15,472,000 | 15,706,000 |  |
Provisions | 9,684,000 |  | 897,000 |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (1,653,000) |  | (1,689,000) |  |
Recoveries | 717,000 |  | 558,000 |  |
Ending balance | 44,098,000 | 18,232,000 | 15,472,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 44,098,000 | 15,472,000 | 15,472,000 | 44,098,000 |
Consumer Portfolio Segment | Residential Mortgage | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 17,118,000 |  |  |  |
Ending balance |  | 17,118,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 17,118,000 | 17,118,000 |  |  |
Consumer Portfolio Segment | Residential Mortgage | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 35,350,000 |  |  |  |
Ending balance |  | 35,350,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 35,350,000 | 35,350,000 |  |  |
Consumer Portfolio Segment | Revolving Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 19,702,000 | 21,862,000 | 22,436,000 |  |
Provisions | 1,134,000 |  | 1,112,000 |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (1,662,000) |  | (3,235,000) |  |
Recoveries | 1,918,000 |  | 1,549,000 |  |
Ending balance | 24,757,000 | 19,702,000 | 21,862,000 |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 24,757,000 | 21,862,000 | $ 21,862,000 | 24,757,000 |
Consumer Portfolio Segment | Revolving Mortgage | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 3,665,000 |  |  |  |
Ending balance |  | 3,665,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 3,665,000 | 3,665,000 |  |  |
Consumer Portfolio Segment | Revolving Mortgage | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 23,367,000 |  |  |  |
Ending balance |  | 23,367,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 23,367,000 | 23,367,000 |  |  |
Consumer Portfolio Segment | Consumer Auto Loan |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 4,292,000 |  |  |  |
Provisions | 6,297,000 |  |  |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (3,646,000) |  |  |  |
Recoveries | 1,417,000 |  |  |  |
Ending balance | 9,460,000 | 4,292,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 9,460,000 | 4,292,000 |  | 9,460,000 |
Consumer Portfolio Segment | Consumer Auto Loan | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 1,100,000 |  |  |  |
Ending balance |  | 1,100,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 1,100,000 | 1,100,000 |  |  |
Consumer Portfolio Segment | Consumer Auto Loan | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 5,392,000 |  |  |  |
Ending balance |  | 5,392,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 5,392,000 | 5,392,000 |  |  |
Consumer Portfolio Segment | Consumer Loan, Other |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 30,301,000 |  |  |  |
Provisions | 10,410,000 |  |  |  |
Initial PCD allowance | 0 |  |  |  |
Charge-offs | (17,188,000) |  |  |  |
Recoveries | 5,879,000 |  |  |  |
Ending balance | 39,439,000 | 30,301,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 39,439,000 | 30,301,000 |  | 39,439,000 |
Consumer Portfolio Segment | Consumer Loan, Other | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 10,037,000 |  |  |  |
Ending balance |  | 10,037,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 10,037,000 | 10,037,000 |  |  |
Consumer Portfolio Segment | Consumer Loan, Other | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 40,338,000 |  |  |  |
Ending balance |  | 40,338,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 40,338,000 | 40,338,000 |  |  |
Unfunded Loan Commitment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 1,055,000 |  |  |  |
Provisions | 2,874,000 |  |  |  |
Ending balance | 12,814,000 | 1,055,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 12,814,000 | 1,055,000 |  | $ 12,814,000 |
Unfunded Loan Commitment | Cumulative Effect, Period of Adoption, Adjustment |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 8,885,000 |  |  |  |
Ending balance |  | 8,885,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 8,885,000 | 8,885,000 |  |  |
Unfunded Loan Commitment | Cumulative Effect, Period of Adoption, Adjusted Balance |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 9,940,000 |  |  |  |
Ending balance |  | 9,940,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 9,940,000 | 9,940,000 |  |  |
Non-PCI Loans |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 225,141,000 |  |  |  |
Provisions |  | 31,441,000 |  |  |
Charge-offs |  | (43,027,000) |  |  |
Recoveries |  | 13,015,000 |  |  |
Ending balance |  | 225,141,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 225,141,000 | 225,141,000 |  |  |
Non-PCI Loans | Commercial | Construction and land development |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 33,213,000 |  |  |  |
Provisions |  | (2,171,000) |  |  |
Charge-offs |  | (196,000) |  |  |
Recoveries |  | 310,000 |  |  |
Ending balance |  | 33,213,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 33,213,000 | 33,213,000 |  |  |
Non-PCI Loans | Commercial | Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 45,335,000 |  |  |  |
Provisions |  | 2,384,000 |  |  |
Charge-offs |  | (1,096,000) |  |  |
Recoveries |  | 596,000 |  |  |
Ending balance |  | 45,335,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 45,335,000 | 45,335,000 |  |  |
Non-PCI Loans | Commercial | Other commercial real estate |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,211,000 |  |  |  |
Provisions |  | (285,000) |  |  |
Charge-offs |  | 0 |  |  |
Recoveries |  | 15,000 |  |  |
Ending balance |  | 2,211,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,211,000 | 2,211,000 |  |  |
Non-PCI Loans | Commercial | Commercial and industrial |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 59,374,000 |  |  |  |
Provisions |  | 14,212,000 |  |  |
Charge-offs |  | (13,352,000) |  |  |
Recoveries |  | 2,894,000 |  |  |
Ending balance |  | 59,374,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 59,374,000 | 59,374,000 |  |  |
Non-PCI Loans | Commercial | Other |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,236,000 |  |  |  |
Provisions |  | (754,000) |  |  |
Charge-offs |  | (100,000) |  |  |
Recoveries |  | 869,000 |  |  |
Ending balance |  | 2,236,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,236,000 | 2,236,000 |  |  |
Non-PCI Loans | Consumer Portfolio Segment | Construction and land development |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 2,709,000 |  |  |  |
Provisions |  | 359,000 |  |  |
Charge-offs |  | 0 |  |  |
Recoveries |  | 0 |  |  |
Ending balance |  | 2,709,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 2,709,000 | 2,709,000 |  |  |
Non-PCI Loans | Consumer Portfolio Segment | Consumer |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 34,593,000 |  |  |  |
Provisions |  | 16,611,000 |  |  |
Charge-offs |  | (24,562,000) |  |  |
Recoveries |  | 6,703,000 |  |  |
Ending balance |  | 34,593,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 34,593,000 | 34,593,000 |  |  |
Non-PCI Loans | Consumer Portfolio Segment | Residential Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 18,232,000 |  |  |  |
Provisions |  | 3,481,000 |  |  |
Charge-offs |  | (1,137,000) |  |  |
Recoveries |  | 416,000 |  |  |
Ending balance |  | 18,232,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 18,232,000 | 18,232,000 |  |  |
Non-PCI Loans | Consumer Portfolio Segment | Revolving Mortgage |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 19,702,000 |  |  |  |
Provisions |  | (788,000) |  |  |
Charge-offs |  | (2,584,000) |  |  |
Recoveries |  | 1,212,000 |  |  |
Ending balance |  | 19,702,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | 19,702,000 | 19,702,000 |  |  |
PCD Loans |  |  |  |  |
Allowance for Loan and Lease Losses [Roll Forward] |  |  |  |  |
Beginning balance | 7,536,000 |  |  |  |
Ending balance |  | 7,536,000 |  |  |
Allowance for Loans and Leases Evaluated for Impairment [Abstract] |  |  |  |  |
Increase (decrease) in allowance for credit loss | $ 7,536,000 | $ 7,536,000 |  |  |

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