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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Jun. 30, 2019 | Dec. 31, 2018
--- | --- | ---
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | $ 7,052 | $ 40,674
Past due | 36,122 | 75,833
Loans, current | 6,806,579 | 6,485,456
Total loans | 6,842,701 | 6,561,289
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 10,876 | 15,978
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 8,237 | 6,011
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 17,009 | 53,844
Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,312 | 10,890
Past due | 12,696 | 25,591
Loans, current | 1,190,047 | 1,103,378
Total loans | 1,202,743 | 1,128,969
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,160 | 4,651
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 696 | 1,089
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 8,840 | 19,851
Commercial Real Estate:Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 206 | 16
Past due | 1,338 | 3,356
Loans, current | 2,008,860 | 1,882,875
Total loans | 2,010,198 | 1,886,231
Commercial Real Estate:Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 308 | 727
Commercial Real Estate:Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due |  | 1,707
Commercial Real Estate:Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,030 | 922
Commercial Real Estate: Farmland and Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 325 | 24,910
Past due | 7,145 | 30,951
Loans, current | 2,020,851 | 1,918,947
Total loans | 2,027,996 | 1,949,898
Commercial Real Estate: Farmland and Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,534 | 2,928
Commercial Real Estate: Farmland and Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 4,844 | 784
Commercial Real Estate: Farmland and Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 767 | 27,239
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing |  | 71
Past due | 660 | 1,505
Loans, current | 220,771 | 224,752
Total loans | 221,431 | 226,257
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due |  | 927
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 155 |
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 505 | 578
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 3,948 | 3,079
Past due | 8,363 | 9,037
Loans, current | 451,815 | 436,763
Total loans | 460,178 | 445,800
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 2,632 | 3,998
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,419 | 1,677
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,312 | 3,362
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,070 | 937
Past due | 2,367 | 2,881
Loans, current | 722,897 | 724,420
Total loans | 725,264 | 727,301
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 633 | 1,155
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 374 | 618
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,360 | 1,108
Consumer |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 24 | 32
Past due | 881 | 550
Loans, current | 45,832 | 45,766
Total loans | 46,713 | 46,316
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 742 | 486
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 111 | 19
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 28 | 45
Foreign |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 167 | 739
Past due | 2,672 | 1,962
Loans, current | 145,506 | 148,555
Total loans | 148,178 | 150,517
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,867 | 1,106
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 638 | 117
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 167 | $ 739

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