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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) | Dec. 31, 2016 | Dec. 31, 2015 | Dec. 31, 2014
--- | --- | --- | ---
Financing receivable recorded investment |  |  |
Past due | $ 61,400,000 | $ 68,273,000 |
Past due 90 days or Greater and Still Accruing | 5,226,000 | 11,616,000 | $ 9,988,000
Loans, current | 5,903,288,000 | 5,882,641,000 |
Total loans | 5,964,688,000 | 5,950,914,000 |
30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 17,299,000 | 15,584,000 |
60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 6,327,000 | 5,219,000 |
90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 37,774,000 | 47,470,000 |
Commercial |  |  |
Financing receivable recorded investment |  |  |
Past due | 26,033,000 | 32,916,000 |
Past due 90 days or Greater and Still Accruing | 392,000 | 2,566,000 |
Loans, current | 883,634,000 | 933,936,000 |
Total loans | 909,667,000 | 966,852,000 |
Commercial | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 4,081,000 | 3,361,000 |
Commercial | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 829,000 | 940,000 |
Commercial | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 21,123,000 | 28,615,000 |
Commercial Real Estate: Other Construction and Land Development |  |  |
Financing receivable recorded investment |  |  |
Past due | 6,354,000 | 3,988,000 |
Past due 90 days or Greater and Still Accruing | 9,000 |  |
Loans, current | 1,710,521,000 | 1,645,839,000 |
Total loans | 1,716,875,000 | 1,649,827,000 |
Commercial Real Estate: Other Construction and Land Development | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,502,000 | 193,000 |
Commercial Real Estate: Other Construction and Land Development | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 396,000 | 293,000 |
Commercial Real Estate: Other Construction and Land Development | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 4,456,000 | 3,502,000 |
Commercial Real Estate: Farmland & Commercial |  |  |
Financing receivable recorded investment |  |  |
Past due | 12,658,000 | 12,304,000 |
Past due 90 days or Greater and Still Accruing | 289,000 | 3,373,000 |
Loans, current | 1,930,412,000 | 1,983,144,000 |
Total loans | 1,943,070,000 | 1,995,448,000 |
Commercial Real Estate: Farmland & Commercial | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 3,454,000 | 2,684,000 |
Commercial Real Estate: Farmland & Commercial | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 3,054,000 | 1,328,000 |
Commercial Real Estate: Farmland & Commercial | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 6,150,000 | 8,292,000 |
Commercial Real Estate: Multifamily |  |  |
Financing receivable recorded investment |  |  |
Past due | 596,000 | 1,317,000 |
Past due 90 days or Greater and Still Accruing |  | 49,000 |
Loans, current | 139,870,000 | 138,131,000 |
Total loans | 140,466,000 | 139,448,000 |
Commercial Real Estate: Multifamily | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 44,000 | 49,000 |
Commercial Real Estate: Multifamily | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due |  | 442,000 |
Commercial Real Estate: Multifamily | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 552,000 | 826,000 |
Residential First Lien |  |  |
Financing receivable recorded investment |  |  |
Past due | 11,108,000 | 11,139,000 |
Past due 90 days or Greater and Still Accruing | 3,756,000 | 4,093,000 |
Loans, current | 410,796,000 | 399,105,000 |
Total loans | 421,904,000 | 410,244,000 |
Residential First Lien | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 5,615,000 | 5,299,000 |
Residential First Lien | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,350,000 | 1,545,000 |
Residential First Lien | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 4,143,000 | 4,295,000 |
Residential Junior Lien |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,480,000 | 1,772,000 |
Past due 90 days or Greater and Still Accruing | 382,000 | 640,000 |
Loans, current | 608,838,000 | 550,566,000 |
Total loans | 610,318,000 | 552,338,000 |
Residential Junior Lien | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 762,000 | 713,000 |
Residential Junior Lien | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 178,000 | 413,000 |
Residential Junior Lien | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 540,000 | 646,000 |
Consumer |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,418,000 | 1,308,000 |
Past due 90 days or Greater and Still Accruing | 387,000 | 453,000 |
Loans, current | 53,750,000 | 56,436,000 |
Total loans | 55,168,000 | 57,744,000 |
Consumer | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 910,000 | 646,000 |
Consumer | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 95,000 | 175,000 |
Consumer | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | 413,000 | 487,000 |
Foreign |  |  |
Financing receivable recorded investment |  |  |
Past due | 1,753,000 | 3,529,000 |
Past due 90 days or Greater and Still Accruing | 11,000 | 442,000 |
Loans, current | 165,467,000 | 175,484,000 |
Total loans | 167,220,000 | 179,013,000 |
Foreign | 30 to 59 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 931,000 | 2,639,000 |
Foreign | 60 to 89 Days |  |  |
Financing receivable recorded investment |  |  |
Past due | 425,000 | 83,000 |
Foreign | 90 Days or Greater |  |  |
Financing receivable recorded investment |  |  |
Past due | $ 397,000 | $ 807,000 |

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