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Loans and Allowances for Credit Losses, Credit Quality Indicators (Details) - USD ($) $ in Thousands | Dec. 31, 2019 | Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | --- | --- | ---
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | $ 19,826,731 | $ 19,805,403 |  |
Non-Graded, Recorded Investment | 1,924,256 | 1,851,327 |  |
Total | 21,750,987 | 21,656,730 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 179,129 | 171,272 |  |
Non-Graded, Related Allowance | 14,435 | 18,417 |  |
Total, Related Allowance | 210,759 | 207,457 | $ 230,682 | $ 246,159
Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 13,997,538 | 13,586,654 |  |
Non-Graded, Recorded Investment | 34,112 | 49,424 |  |
Total | 14,031,650 | 13,636,078 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 117,236 | 101,303 |  |
Non-Graded, Related Allowance | 951 | 923 |  |
Total, Related Allowance | 118,187 | 102,226 | 124,269 | 140,213
Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 3,973,377 | 3,590,333 |  |
Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 3,122,163 | 3,258,192 |  |
Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 1,760,866 | 1,621,158 |  |
Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 665,449 | 730,521 |  |
Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 3,033,916 | 2,799,277 |  |
Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 709,868 | 804,550 |  |
Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 766,011 | 832,047 |  |
Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 4,433,783 | 4,764,813 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Total | 4,433,783 | 4,764,813 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 51,805 | 60,026 |  |
Non-Graded, Related Allowance | 0 | 0 |  |
Total, Related Allowance | 51,805 | 60,026 | 56,621 | 50,749
Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 150,879 | 148,584 |  |
Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 775,521 | 919,082 |  |
Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 928,379 | 1,072,920 |  |
Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 1,265,562 | 1,288,065 |  |
Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 856,117 | 778,106 |  |
Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 457,325 | 558,056 |  |
Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 279,113 | 505,046 |  |
Non-Graded, Recorded Investment | 1,805,059 | 1,724,987 |  |
Total | 2,084,172 | 2,230,033 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 3,085 | 3,310 |  |
Non-Graded, Related Allowance | 11,315 | 14,654 |  |
Total, Related Allowance | 14,400 | 17,964 | 18,451 | 18,224
Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 1,057,321 | 1,122,610 |  |
Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 197,794 | 190,866 |  |
Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Total | 829,057 | 916,557 |  |
Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,116,297 | 948,890 |  |
Non-Graded, Recorded Investment | 85,085 | 76,916 |  |
Total | 1,201,382 | 1,025,806 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 7,003 | 6,633 |  |
Non-Graded, Related Allowance | 2,169 | 2,840 |  |
Total, Related Allowance | 9,172 | 9,473 | 9,124 | 8,773
Specific Allowance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 19,826,731 | 19,805,403 |  |
Non-Graded, Recorded Investment | 1,924,256 | 1,851,327 |  |
Total | 21,750,987 | 21,656,730 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 179,129 | 171,272 |  |
Non-Graded, Related Allowance | 14,435 | 18,417 |  |
Total, Related Allowance | 193,564 | 189,689 |  |
Nonspecific Allowance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Total | 0 | 0 |  |
Related Allowance [Abstract] |  |  |  |
Internally Risk Graded, Related Allowance | 0 | 0 |  |
Non-Graded, Related Allowance | 0 | 0 |  |
Total, Related Allowance | 17,195 | 17,768 | $ 22,217 | $ 28,200
Performing Financial Instruments [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 1,886,858 | 1,811,557 |  |
Performing Financial Instruments [Member] | Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 34,075 | 49,371 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 34,075 | 49,371 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 1,767,930 | 1,685,424 |  |
Performing Financial Instruments [Member] | Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 758,260 | 819,199 |  |
Performing Financial Instruments [Member] | Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 191,694 | 183,734 |  |
Performing Financial Instruments [Member] | Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 817,976 | 682,491 |  |
Performing Financial Instruments [Member] | Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 84,853 | 76,762 |  |
Performing Financial Instruments [Member] | Pass [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 19,312,702 | 19,285,126 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 13,538,705 | 13,135,068 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 3,700,406 | 3,414,039 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 3,050,946 | 3,167,203 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,749,023 | 1,593,902 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 623,219 | 668,438 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 2,995,514 | 2,730,121 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 709,868 | 804,550 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 709,729 | 756,815 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 4,381,663 | 4,712,826 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 150,529 | 148,234 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 743,343 | 885,588 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 923,202 | 1,059,334 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,257,005 | 1,287,471 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 852,539 | 776,898 |  |
Performing Financial Instruments [Member] | Pass [Member] | Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 455,045 | 555,301 |  |
Performing Financial Instruments [Member] | Pass [Member] | Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 276,138 | 492,976 |  |
Performing Financial Instruments [Member] | Pass [Member] | Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 276,138 | 269,678 |  |
Performing Financial Instruments [Member] | Pass [Member] | Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Pass [Member] | Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 223,298 |  |
Performing Financial Instruments [Member] | Pass [Member] | Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,116,196 | 944,256 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 210,149 | 181,960 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 187,881 | 157,866 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 117,298 | 42,176 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 29,943 | 49,761 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 5,281 | 18,809 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 18,214 | 30,934 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 13,117 | 14,920 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 4,028 | 1,266 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 22,145 | 23,927 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 12,067 | 11,926 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 5,177 | 10,532 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,604 | 281 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,658 | 0 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,639 | 1,188 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 78 | 52 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 78 | 52 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Other Loans Especially Mentioned [Member] | Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 45 | 115 |  |
Performing Financial Instruments [Member] | Substandard [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 160,326 | 214,840 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 155,573 | 193,932 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 63,951 | 86,624 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 33,791 | 32,661 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 5,399 | 7,131 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 13,883 | 22,230 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 20,805 | 37,698 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 17,744 | 7,588 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 2,349 | 6,439 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,243 | 1,289 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 3,054 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 95 | 12 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,011 | 1,208 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 876 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 2,404 | 10,026 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 2,404 | 9,730 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 296 |  |
Performing Financial Instruments [Member] | Substandard [Member] | Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 4,443 |  |
Nonaccrual [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 143,554 | 123,476 |  |
Non-Graded, Recorded Investment | 37,398 | 39,771 |  |
Nonaccrual [Member] | Commercial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 115,379 | 99,788 |  |
Non-Graded, Recorded Investment | 37 | 53 |  |
Nonaccrual [Member] | Commercial [Member] | Energy [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 91,722 | 47,494 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Services [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 7,483 | 8,567 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Wholesale/retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 1,163 | 1,316 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Manufacturing [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 10,133 | 8,919 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Healthcare [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 4,480 | 16,538 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Public finance [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial [Member] | Other commercial and industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 398 | 16,954 |  |
Non-Graded, Recorded Investment | 37 | 53 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 27,626 | 21,621 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Residential construction and land development [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 350 | 350 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Retail [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 18,868 | 20,279 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Office [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Multifamily [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 6,858 | 301 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Industrial [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 909 | 0 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Commercial Real Estate [Member] | Other commercial real estate [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 641 | 691 |  |
Non-Graded, Recorded Investment | 0 | 0 |  |
Nonaccrual [Member] | Residential Mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 493 | 1,991 |  |
Non-Graded, Recorded Investment | 37,129 | 39,564 |  |
Nonaccrual [Member] | Residential Mortgage [Member] | Permanent mortgage [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 493 | 1,991 |  |
Non-Graded, Recorded Investment | 19,948 | 21,960 |  |
Nonaccrual [Member] | Residential Mortgage [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Non-Graded, Recorded Investment | 6,100 | 7,132 |  |
Nonaccrual [Member] | Residential Mortgage [Member] | Home equity [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 0 | 0 |  |
Non-Graded, Recorded Investment | 11,081 | 10,472 |  |
Nonaccrual [Member] | Personal [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Internally Risk Graded, Recorded Investment | 56 | 76 |  |
Non-Graded, Recorded Investment | 232 | 154 |  |
Residential Mortgage [Member] | Performing Financial Instruments [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | 192,000 | 184,000 |  |
Residential Mortgage [Member] | Nonaccrual [Member] | Permanent mortgages guaranteed by U.S. government agencies [Member] |  |  |  |
Recorded Investment [Abstract] |  |  |  |
Non-Graded, Recorded Investment | $ 6,100 | $ 7,100 |  |

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