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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Sep. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | $ 7,626 | $ 40,674
Past due | 116,561 | 75,833
Loans, current | 6,778,581 | 6,485,456
Total loans | 6,895,142 | 6,561,289
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 22,870 | 15,978
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 77,913 | 6,011
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 15,778 | 53,844
Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,477 | 10,890
Past due | 11,803 | 25,591
Loans, current | 1,283,933 | 1,103,378
Total loans | 1,295,736 | 1,128,969
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,493 | 4,651
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 902 | 1,089
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 7,408 | 19,851
Commercial Real Estate:Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 286 | 16
Past due | 28,581 | 3,356
Loans, current | 2,015,829 | 1,882,875
Total loans | 2,044,410 | 1,886,231
Commercial Real Estate:Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 8,977 | 727
Commercial Real Estate:Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 18,504 | 1,707
Commercial Real Estate:Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,100 | 922
Commercial Real Estate: Farmland and Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 737 | 24,910
Past due | 60,605 | 30,951
Loans, current | 1,906,506 | 1,918,947
Total loans | 1,967,111 | 1,949,898
Commercial Real Estate: Farmland and Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,210 | 2,928
Commercial Real Estate: Farmland and Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 56,125 | 784
Commercial Real Estate: Farmland and Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,270 | 27,239
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 764 | 71
Past due | 1,579 | 1,505
Loans, current | 240,510 | 224,752
Total loans | 242,089 | 226,257
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 24 | 927
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 290 |
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,265 | 578
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 2,930 | 3,079
Past due | 7,433 | 9,037
Loans, current | 431,039 | 436,763
Total loans | 438,472 | 445,800
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,961 | 3,998
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,169 | 1,677
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 3,303 | 3,362
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,216 | 937
Past due | 2,837 | 2,881
Loans, current | 710,455 | 724,420
Total loans | 713,292 | 727,301
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,316 | 1,155
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 305 | 618
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,216 | 1,108
Consumer |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 69 | 32
Past due | 967 | 550
Loans, current | 46,105 | 45,766
Total loans | 47,072 | 46,316
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 770 | 486
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 128 | 19
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 69 | 45
Foreign |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 147 | 739
Past due | 2,756 | 1,962
Loans, current | 144,204 | 148,555
Total loans | 146,960 | 150,517
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,119 | 1,106
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 490 | 117
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 147 | $ 739

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