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Loans and Allowances for Credit Losses, Credit Quality Indicators (Details) - USD ($) $ in Thousands | Jun. 30, 2020 | Dec. 31, 2019 | Jun. 30, 2019 | Mar. 31, 2019 | Dec. 31, 2018
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Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | $ 3,607,903 |  |  |  |
Financing Receivable, Originated, 2019 | 3,294,567 |  |  |  |
Financing Receivable, Originated, 2018 | 2,919,965 |  |  |  |
Financing Receivable, Originated, 2017 | 2,045,958 |  |  |  |
Financing Receivable, Originated, 2016 | 1,522,705 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 3,620,215 |  |  |  |
Financing Receivable, Revolving | 7,112,055 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 32,522 |  |  |  |
Total | 24,155,890 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | $ 19,826,731 |  |  |
Non-Graded, Recorded Investment |  | 1,924,256 |  |  |
Total | 24,155,890 | 21,750,987 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 179,129 |  |  |
Non-Graded, Allowance |  | 14,435 |  |  |
Total | 435,597 | 210,759 | $ 202,534 | $ 205,340 | $ 207,457
Commercial [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 830,476 |  |  |  |
Financing Receivable, Originated, 2019 | 1,717,640 |  |  |  |
Financing Receivable, Originated, 2018 | 1,614,431 |  |  |  |
Financing Receivable, Originated, 2017 | 1,162,047 |  |  |  |
Financing Receivable, Originated, 2016 | 819,528 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 1,970,813 |  |  |  |
Financing Receivable, Revolving | 6,040,212 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 3,363 |  |  |  |
Total | 14,158,510 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 13,997,538 |  |  |
Non-Graded, Recorded Investment |  | 34,112 |  |  |
Total | 14,158,510 | 14,031,650 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 117,236 |  |  |
Non-Graded, Allowance |  | 951 |  |  |
Total | 310,422 | 118,187 | 106,397 | 103,577 | 102,226
Commercial [Member] | Energy [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 23,119 |  |  |  |
Financing Receivable, Originated, 2019 | 68,836 |  |  |  |
Financing Receivable, Originated, 2018 | 119,626 |  |  |  |
Financing Receivable, Originated, 2017 | 8,344 |  |  |  |
Financing Receivable, Originated, 2016 | 1,476 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 41,233 |  |  |  |
Financing Receivable, Revolving | 3,711,540 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 3,974,174 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 3,974,174 | 3,973,377 |  |  |
Commercial [Member] | Healthcare [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 212,781 |  |  |  |
Financing Receivable, Originated, 2019 | 640,451 |  |  |  |
Financing Receivable, Originated, 2018 | 649,536 |  |  |  |
Financing Receivable, Originated, 2017 | 493,783 |  |  |  |
Financing Receivable, Originated, 2016 | 248,255 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 795,390 |  |  |  |
Financing Receivable, Revolving | 249,147 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 3,289,343 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 3,289,343 | 3,033,916 |  |  |
Commercial [Member] | Services [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 336,059 |  |  |  |
Financing Receivable, Originated, 2019 | 494,582 |  |  |  |
Financing Receivable, Originated, 2018 | 466,100 |  |  |  |
Financing Receivable, Originated, 2017 | 387,982 |  |  |  |
Financing Receivable, Originated, 2016 | 414,269 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 873,472 |  |  |  |
Financing Receivable, Revolving | 806,744 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 673 |  |  |  |
Total | 3,779,881 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 3,779,881 | 3,122,163 |  |  |
Commercial [Member] | General business [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 258,517 |  |  |  |
Financing Receivable, Originated, 2019 | 513,771 |  |  |  |
Financing Receivable, Originated, 2018 | 379,169 |  |  |  |
Financing Receivable, Originated, 2017 | 271,938 |  |  |  |
Financing Receivable, Originated, 2016 | 155,528 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 260,718 |  |  |  |
Financing Receivable, Revolving | 1,272,781 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 2,690 |  |  |  |
Total | 3,115,112 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 3,115,112 |  |  |  |
Commercial [Member] | Wholesale/retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 1,760,866 |  |  |
Commercial [Member] | Manufacturing [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 665,449 |  |  |
Commercial [Member] | Public finance [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 709,868 |  |  |
Commercial [Member] | Other commercial and industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 766,011 |  |  |
Commercial real estate [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 345,439 |  |  |  |
Financing Receivable, Originated, 2019 | 1,131,573 |  |  |  |
Financing Receivable, Originated, 2018 | 1,037,584 |  |  |  |
Financing Receivable, Originated, 2017 | 555,707 |  |  |  |
Financing Receivable, Originated, 2016 | 387,951 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 856,171 |  |  |  |
Financing Receivable, Revolving | 239,719 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 4,554,144 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 4,433,783 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Total | 4,554,144 | 4,433,783 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 51,805 |  |  |
Non-Graded, Allowance |  | 0 |  |  |
Total | 68,756 | 51,805 | 54,188 | 58,134 | 60,026
Commercial real estate [Member] | Residential construction and land development [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 150,879 |  |  |
Commercial real estate [Member] | Retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 775,521 |  |  |
Commercial real estate [Member] | Office [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 928,379 |  |  |
Commercial real estate [Member] | Multifamily [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 1,265,562 |  |  |
Commercial real estate [Member] | Industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 856,117 |  |  |
Commercial real estate [Member] | Other commercial real estate [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 457,325 |  |  |
Paycheck Protection Program |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 2,081,428 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 0 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 2,081,428 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 2,081,428 |  |  |  |
Related Allowance [Abstract] |  |  |  |  |
Total | 0 |  |  |  |
Loans to individuals [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 350,560 |  |  |  |
Financing Receivable, Originated, 2019 | 445,354 |  |  |  |
Financing Receivable, Originated, 2018 | 267,950 |  |  |  |
Financing Receivable, Originated, 2017 | 328,204 |  |  |  |
Financing Receivable, Originated, 2016 | 315,226 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 793,231 |  |  |  |
Financing Receivable, Revolving | 832,124 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 29,159 |  |  |  |
Total | 3,361,808 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 3,361,808 | 2,084,172 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Total | 56,419 |  |  |  |
Loans to individuals [Member] | Permanent Residential Mortgage [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 1,057,321 |  |  |
Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 197,794 |  |  |
Loans to individuals [Member] | Home Equity Loan [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total |  | 829,057 |  |  |
Loans to individuals [Member] | Residential mortgage [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 226,396 |  |  |  |
Financing Receivable, Originated, 2019 | 191,932 |  |  |  |
Financing Receivable, Originated, 2018 | 164,941 |  |  |  |
Financing Receivable, Originated, 2017 | 188,395 |  |  |  |
Financing Receivable, Originated, 2016 | 197,412 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 464,836 |  |  |  |
Financing Receivable, Revolving | 352,109 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 27,421 |  |  |  |
Total | 1,813,442 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 279,113 |  |  |
Non-Graded, Recorded Investment |  | 1,805,059 |  |  |
Total | 1,813,442 | 2,084,172 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 3,085 |  |  |
Non-Graded, Allowance |  | 11,315 |  |  |
Total |  | 14,400 | 15,724 | 15,668 | 17,964
Loans to individuals [Member] | Residential mortgage [Member] | US Government Agency Insured Loans [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 751 |  |  |  |
Financing Receivable, Originated, 2019 | 6,794 |  |  |  |
Financing Receivable, Originated, 2018 | 19,922 |  |  |  |
Financing Receivable, Originated, 2017 | 24,184 |  |  |  |
Financing Receivable, Originated, 2016 | 46,676 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 223,942 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 322,269 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Total | 322,269 |  |  |  |
Loans to individuals [Member] | Personal [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 123,413 |  |  |  |
Financing Receivable, Originated, 2019 | 246,628 |  |  |  |
Financing Receivable, Originated, 2018 | 83,087 |  |  |  |
Financing Receivable, Originated, 2017 | 115,625 |  |  |  |
Financing Receivable, Originated, 2016 | 71,138 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 104,453 |  |  |  |
Financing Receivable, Revolving | 480,015 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 1,738 |  |  |  |
Total | 1,226,097 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,116,297 |  |  |
Non-Graded, Recorded Investment |  | 85,085 |  |  |
Total | 1,226,097 | 1,201,382 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 7,003 |  |  |
Non-Graded, Allowance |  | 2,169 |  |  |
Total |  | 9,172 | 9,388 | 8,783 | 9,473
Specific Allowance [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 19,826,731 |  |  |
Non-Graded, Recorded Investment |  | 1,924,256 |  |  |
Total |  | 21,750,987 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 179,129 |  |  |
Non-Graded, Allowance |  | 14,435 |  |  |
Total |  | 193,564 |  |  |
Nonspecific Allowance [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Total |  | 0 |  |  |
Related Allowance [Abstract] |  |  |  |  |
Internally Risk Graded, Allowance |  | 0 |  |  |
Non-Graded, Allowance |  | 0 |  |  |
Total |  | 17,195 | $ 16,837 | $ 19,178 | $ 17,768
Performing [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 1,886,858 |  |  |
Performing [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 19,312,702 |  |  |
Performing [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 210,149 |  |  |
Performing [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 160,326 |  |  |
Performing [Member] | Commercial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 34,075 |  |  |
Performing [Member] | Commercial [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 13,538,705 |  |  |
Performing [Member] | Commercial [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 187,881 |  |  |
Performing [Member] | Commercial [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 155,573 |  |  |
Performing [Member] | Commercial [Member] | Energy [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Energy [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 23,119 |  |  |  |
Financing Receivable, Originated, 2019 | 62,250 |  |  |  |
Financing Receivable, Originated, 2018 | 94,216 |  |  |  |
Financing Receivable, Originated, 2017 | 8,344 |  |  |  |
Financing Receivable, Originated, 2016 | 1,427 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 2,908 |  |  |  |
Financing Receivable, Revolving | 2,664,680 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 2,856,944 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 3,700,406 |  |  |
Performing [Member] | Commercial [Member] | Energy [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 9,720 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 0 |  |  |  |
Financing Receivable, Revolving | 493,719 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 503,439 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 117,298 |  |  |
Performing [Member] | Commercial [Member] | Energy [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 194 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 49 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 0 |  |  |  |
Financing Receivable, Revolving | 450,559 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 450,802 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 63,951 |  |  |
Performing [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Healthcare [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 212,781 |  |  |  |
Financing Receivable, Originated, 2019 | 609,757 |  |  |  |
Financing Receivable, Originated, 2018 | 641,607 |  |  |  |
Financing Receivable, Originated, 2017 | 489,096 |  |  |  |
Financing Receivable, Originated, 2016 | 248,094 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 767,193 |  |  |  |
Financing Receivable, Revolving | 245,123 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 3,213,651 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 2,995,514 |  |  |
Performing [Member] | Commercial [Member] | Healthcare [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 27,500 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 3,714 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 13,771 |  |  |  |
Financing Receivable, Revolving | 3,515 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 48,500 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 13,117 |  |  |
Performing [Member] | Commercial [Member] | Healthcare [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 3,176 |  |  |  |
Financing Receivable, Originated, 2018 | 7,746 |  |  |  |
Financing Receivable, Originated, 2017 | 973 |  |  |  |
Financing Receivable, Originated, 2016 | 161 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 11,491 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 23,547 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 20,805 |  |  |
Performing [Member] | Commercial [Member] | Services [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Services [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 335,961 |  |  |  |
Financing Receivable, Originated, 2019 | 475,608 |  |  |  |
Financing Receivable, Originated, 2018 | 437,812 |  |  |  |
Financing Receivable, Originated, 2017 | 366,772 |  |  |  |
Financing Receivable, Originated, 2016 | 400,480 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 857,564 |  |  |  |
Financing Receivable, Revolving | 743,258 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 673 |  |  |  |
Total | 3,618,128 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 3,050,946 |  |  |
Performing [Member] | Commercial [Member] | Services [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 3,919 |  |  |  |
Financing Receivable, Originated, 2018 | 1,474 |  |  |  |
Financing Receivable, Originated, 2017 | 170 |  |  |  |
Financing Receivable, Originated, 2016 | 4,513 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 3,626 |  |  |  |
Financing Receivable, Revolving | 35,203 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 48,905 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 29,943 |  |  |
Performing [Member] | Commercial [Member] | Services [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 98 |  |  |  |
Financing Receivable, Originated, 2019 | 12,077 |  |  |  |
Financing Receivable, Originated, 2018 | 26,814 |  |  |  |
Financing Receivable, Originated, 2017 | 12,393 |  |  |  |
Financing Receivable, Originated, 2016 | 8,123 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 4,753 |  |  |  |
Financing Receivable, Revolving | 27,558 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 91,816 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 33,791 |  |  |
Performing [Member] | Commercial [Member] | General business [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 256,821 |  |  |  |
Financing Receivable, Originated, 2019 | 485,956 |  |  |  |
Financing Receivable, Originated, 2018 | 359,249 |  |  |  |
Financing Receivable, Originated, 2017 | 256,403 |  |  |  |
Financing Receivable, Originated, 2016 | 147,056 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 251,326 |  |  |  |
Financing Receivable, Revolving | 1,258,843 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 2,671 |  |  |  |
Total | 3,018,325 |  |  |  |
Performing [Member] | Commercial [Member] | General business [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 10,196 |  |  |  |
Financing Receivable, Originated, 2018 | 763 |  |  |  |
Financing Receivable, Originated, 2017 | 11,244 |  |  |  |
Financing Receivable, Originated, 2016 | 941 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 4,046 |  |  |  |
Financing Receivable, Revolving | 3,404 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 30,594 |  |  |  |
Performing [Member] | Commercial [Member] | General business [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 21 |  |  |  |
Financing Receivable, Originated, 2019 | 13,906 |  |  |  |
Financing Receivable, Originated, 2018 | 13,989 |  |  |  |
Financing Receivable, Originated, 2017 | 2,353 |  |  |  |
Financing Receivable, Originated, 2016 | 6,216 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 5,206 |  |  |  |
Financing Receivable, Revolving | 10,165 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 4 |  |  |  |
Total | 51,860 |  |  |  |
Performing [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Wholesale/retail [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,749,023 |  |  |
Performing [Member] | Commercial [Member] | Wholesale/retail [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 5,281 |  |  |
Performing [Member] | Commercial [Member] | Wholesale/retail [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 5,399 |  |  |
Performing [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Manufacturing [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 623,219 |  |  |
Performing [Member] | Commercial [Member] | Manufacturing [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 18,214 |  |  |
Performing [Member] | Commercial [Member] | Manufacturing [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 13,883 |  |  |
Performing [Member] | Commercial [Member] | Public finance [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Public finance [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 709,868 |  |  |
Performing [Member] | Commercial [Member] | Public finance [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Public finance [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 34,075 |  |  |
Performing [Member] | Commercial [Member] | Other commercial and industrial [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 709,729 |  |  |
Performing [Member] | Commercial [Member] | Other commercial and industrial [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 4,028 |  |  |
Performing [Member] | Commercial [Member] | Other commercial and industrial [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 17,744 |  |  |
Performing [Member] | Commercial real estate [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 345,439 |  |  |  |
Financing Receivable, Originated, 2019 | 1,131,573 |  |  |  |
Financing Receivable, Originated, 2018 | 1,037,584 |  |  |  |
Financing Receivable, Originated, 2017 | 536,047 |  |  |  |
Financing Receivable, Originated, 2016 | 378,852 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 852,020 |  |  |  |
Financing Receivable, Revolving | 234,148 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 4,515,663 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 4,381,663 |  |  |
Performing [Member] | Commercial real estate [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 12,200 |  |  |  |
Financing Receivable, Originated, 2016 | 1,622 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 3,283 |  |  |  |
Financing Receivable, Revolving | 100 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 17,205 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 22,145 |  |  |
Performing [Member] | Commercial real estate [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 7,228 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 65 |  |  |  |
Financing Receivable, Revolving | 27 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 7,320 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 2,349 |  |  |
Performing [Member] | Commercial real estate [Member] | Residential construction and land development [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Residential construction and land development [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 150,529 |  |  |
Performing [Member] | Commercial real estate [Member] | Residential construction and land development [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Residential construction and land development [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Retail [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 743,343 |  |  |
Performing [Member] | Commercial real estate [Member] | Retail [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 12,067 |  |  |
Performing [Member] | Commercial real estate [Member] | Retail [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,243 |  |  |
Performing [Member] | Commercial real estate [Member] | Office [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Office [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 923,202 |  |  |
Performing [Member] | Commercial real estate [Member] | Office [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 5,177 |  |  |
Performing [Member] | Commercial real estate [Member] | Office [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Multifamily [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Multifamily [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,257,005 |  |  |
Performing [Member] | Commercial real estate [Member] | Multifamily [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,604 |  |  |
Performing [Member] | Commercial real estate [Member] | Multifamily [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 95 |  |  |
Performing [Member] | Commercial real estate [Member] | Industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Industrial [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 852,539 |  |  |
Performing [Member] | Commercial real estate [Member] | Industrial [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,658 |  |  |
Performing [Member] | Commercial real estate [Member] | Industrial [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,011 |  |  |
Performing [Member] | Commercial real estate [Member] | Other commercial real estate [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Commercial real estate [Member] | Other commercial real estate [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 455,045 |  |  |
Performing [Member] | Commercial real estate [Member] | Other commercial real estate [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,639 |  |  |
Performing [Member] | Commercial real estate [Member] | Other commercial real estate [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Paycheck Protection Program | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 2,081,428 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 0 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 2,081,428 |  |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 758,260 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 276,138 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 78 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 2,404 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 191,694 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Home Equity Loan [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 817,976 |  |  |
Performing [Member] | Loans to individuals [Member] | Home Equity Loan [Member] | Pass [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Home Equity Loan [Member] | Special Mention [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Home Equity Loan [Member] | Accruing Substandard [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Performing [Member] | Loans to individuals [Member] | Residential mortgage [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 1,767,930 |  |  |
Performing [Member] | Loans to individuals [Member] | Residential mortgage [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 226,396 |  |  |  |
Financing Receivable, Originated, 2019 | 191,344 |  |  |  |
Financing Receivable, Originated, 2018 | 161,193 |  |  |  |
Financing Receivable, Originated, 2017 | 187,649 |  |  |  |
Financing Receivable, Originated, 2016 | 196,218 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 438,056 |  |  |  |
Financing Receivable, Revolving | 349,610 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 26,679 |  |  |  |
Total | 1,777,145 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 276,138 |  |  |
Performing [Member] | Loans to individuals [Member] | Residential mortgage [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 2,011 |  |  |  |
Financing Receivable, Originated, 2017 | 192 |  |  |  |
Financing Receivable, Originated, 2016 | 12 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 437 |  |  |  |
Financing Receivable, Revolving | 329 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 2,981 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 78 |  |  |
Performing [Member] | Loans to individuals [Member] | Residential mortgage [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 123 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 40 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 4 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 51 |  |  |  |
Total | 218 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 2,404 |  |  |
Performing [Member] | Loans to individuals [Member] | Residential mortgage [Member] | US Government Agency Insured Loans [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 751 |  |  |  |
Financing Receivable, Originated, 2019 | 6,794 |  |  |  |
Financing Receivable, Originated, 2018 | 19,678 |  |  |  |
Financing Receivable, Originated, 2017 | 24,184 |  |  |  |
Financing Receivable, Originated, 2016 | 46,676 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 218,076 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 316,159 |  |  |  |
Performing [Member] | Loans to individuals [Member] | Personal [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Non-Graded, Recorded Investment |  | 84,853 |  |  |
Performing [Member] | Loans to individuals [Member] | Personal [Member] | Pass [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 123,394 |  |  |  |
Financing Receivable, Originated, 2019 | 246,327 |  |  |  |
Financing Receivable, Originated, 2018 | 83,000 |  |  |  |
Financing Receivable, Originated, 2017 | 115,562 |  |  |  |
Financing Receivable, Originated, 2016 | 71,036 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 99,322 |  |  |  |
Financing Receivable, Revolving | 479,958 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 1,738 |  |  |  |
Total | 1,220,337 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,116,196 |  |  |
Performing [Member] | Loans to individuals [Member] | Personal [Member] | Special Mention [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 50 |  |  |  |
Financing Receivable, Originated, 2018 | 16 |  |  |  |
Financing Receivable, Originated, 2017 | 28 |  |  |  |
Financing Receivable, Originated, 2016 | 55 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 5,087 |  |  |  |
Financing Receivable, Revolving | 10 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 5,246 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 45 |  |  |
Performing [Member] | Loans to individuals [Member] | Personal [Member] | Accruing Substandard [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 19 |  |  |  |
Financing Receivable, Originated, 2019 | 229 |  |  |  |
Financing Receivable, Originated, 2018 | 11 |  |  |  |
Financing Receivable, Originated, 2017 | 6 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 0 |  |  |  |
Financing Receivable, Revolving | 16 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 281 |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 143,554 |  |  |
Non-Graded, Recorded Investment |  | 37,398 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 115,379 |  |  |
Non-Graded, Recorded Investment |  | 37 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Energy [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 91,722 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Energy [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 6,586 |  |  |  |
Financing Receivable, Originated, 2018 | 15,496 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 38,325 |  |  |  |
Financing Receivable, Revolving | 102,582 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 162,989 |  |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 4,480 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Healthcare [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 18 |  |  |  |
Financing Receivable, Originated, 2018 | 183 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 2,935 |  |  |  |
Financing Receivable, Revolving | 509 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 3,645 |  |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Services [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 7,483 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Services [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 2,978 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 8,647 |  |  |  |
Financing Receivable, Originated, 2016 | 1,153 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 7,529 |  |  |  |
Financing Receivable, Revolving | 725 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 21,032 |  |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | General business [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 1,675 |  |  |  |
Financing Receivable, Originated, 2019 | 3,713 |  |  |  |
Financing Receivable, Originated, 2018 | 5,168 |  |  |  |
Financing Receivable, Originated, 2017 | 1,938 |  |  |  |
Financing Receivable, Originated, 2016 | 1,315 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 140 |  |  |  |
Financing Receivable, Revolving | 369 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 15 |  |  |  |
Total | 14,333 |  |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 1,163 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 10,133 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Public finance [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 398 |  |  |
Non-Graded, Recorded Investment |  | 37 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 27,626 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 0 |  |  |  |
Financing Receivable, Originated, 2017 | 232 |  |  |  |
Financing Receivable, Originated, 2016 | 7,477 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 803 |  |  |  |
Financing Receivable, Revolving | 5,444 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 13,956 |  |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Residential construction and land development [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 350 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Retail [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 18,868 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Office [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Multifamily [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 6,858 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Industrial [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 909 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Commercial real estate [Member] | Other commercial real estate [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 641 |  |  |
Non-Graded, Recorded Investment |  | 0 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 493 |  |  |
Non-Graded, Recorded Investment |  | 19,948 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Permanent Residential Mortgage [Member] | US Government Agency Insured Loans [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Non-Graded, Recorded Investment |  | 6,100 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Home Equity Loan [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 0 |  |  |
Non-Graded, Recorded Investment |  | 11,081 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Residential mortgage [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 493 |  |  |
Non-Graded, Recorded Investment |  | 37,129 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Residential mortgage [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 588 |  |  |  |
Financing Receivable, Originated, 2018 | 1,614 |  |  |  |
Financing Receivable, Originated, 2017 | 554 |  |  |  |
Financing Receivable, Originated, 2016 | 1,142 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 26,339 |  |  |  |
Financing Receivable, Revolving | 2,170 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 691 |  |  |  |
Total | 33,098 |  |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Residential mortgage [Member] | US Government Agency Insured Loans [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 0 |  |  |  |
Financing Receivable, Originated, 2018 | 244 |  |  |  |
Financing Receivable, Originated, 2017 | 0 |  |  |  |
Financing Receivable, Originated, 2016 | 0 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 5,866 |  |  |  |
Financing Receivable, Revolving | 0 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | 6,110 |  |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Personal [Member] |  |  |  |  |
Recorded Investment [Abstract] |  |  |  |  |
Internally Risk Graded, Recorded Investment |  | 56 |  |  |
Non-Graded, Recorded Investment |  | $ 232 |  |  |
Nonperforming Financial Instruments [Member] | Loans to individuals [Member] | Personal [Member] | Nonaccruing substandard and doubtful [Member] |  |  |  |  |
Financing Receivable, Credit Quality Indicator Line Items [Abstract] |  |  |  |  |
Financing Receivable, Originated, 2020 | 0 |  |  |  |
Financing Receivable, Originated, 2019 | 22 |  |  |  |
Financing Receivable, Originated, 2018 | 60 |  |  |  |
Financing Receivable, Originated, 2017 | 29 |  |  |  |
Financing Receivable, Originated, 2016 | 47 |  |  |  |
Financing Receivable, Originated, 2015 or Prior | 44 |  |  |  |
Financing Receivable, Revolving | 31 |  |  |  |
Financing Receivable, Revolving, Converted to Term Loan | 0 |  |  |  |
Total | $ 233 |  |  |  |

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