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Allowance for Probable Loan Losses (Aging By Loan Class) (Details) - USD ($) $ in Thousands | Mar. 31, 2019 | Dec. 31, 2018
--- | --- | ---
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | $ 8,292 | $ 40,674
Past due | 94,889 | 75,833
Loans, current | 6,612,454 | 6,485,456
Total loans | 6,707,343 | 6,561,289
30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 30,159 | 15,978
60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 11,883 | 6,011
90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 52,847 | 53,844
Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 844 | 10,890
Past due | 27,278 | 25,591
Loans, current | 1,186,261 | 1,103,378
Total loans | 1,213,539 | 1,128,969
Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 7,139 | 4,651
Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,412 | 1,089
Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 18,727 | 19,851
Commercial Real Estate:Other Construction and Land Development |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,041 | 16
Past due | 10,427 | 3,356
Loans, current | 1,923,919 | 1,882,875
Total loans | 1,934,346 | 1,886,231
Commercial Real Estate:Other Construction and Land Development | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 7,451 | 727
Commercial Real Estate:Other Construction and Land Development | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,111 | 1,707
Commercial Real Estate:Other Construction and Land Development | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,865 | 922
Commercial Real Estate: Farmland and Commercial |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 401 | 24,910
Past due | 37,106 | 30,951
Loans, current | 1,859,552 | 1,918,947
Total loans | 1,896,658 | 1,949,898
Commercial Real Estate: Farmland and Commercial | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 6,486 | 2,928
Commercial Real Estate: Farmland and Commercial | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 5,292 | 784
Commercial Real Estate: Farmland and Commercial | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 25,328 | 27,239
Commercial Real Estate: Multifamily |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing |  | 71
Past due | 2,567 | 1,505
Loans, current | 291,545 | 224,752
Total loans | 294,112 | 226,257
Commercial Real Estate: Multifamily | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 1,122 | 927
Commercial Real Estate: Multifamily | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 938 |
Commercial Real Estate: Multifamily | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 507 | 578
Residential First Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 4,272 | 3,079
Past due | 9,638 | 9,037
Loans, current | 447,276 | 436,763
Total loans | 456,914 | 445,800
Residential First Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,610 | 3,998
Residential First Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 1,516 | 1,677
Residential First Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 4,512 | 3,362
Residential Junior Lien |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 1,574 | 937
Past due | 3,536 | 2,881
Loans, current | 717,576 | 724,420
Total loans | 721,112 | 727,301
Residential Junior Lien | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 982 | 1,155
Residential Junior Lien | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 815 | 618
Residential Junior Lien | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 1,739 | 1,108
Consumer |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 16 | 32
Past due | 449 | 550
Loans, current | 45,624 | 45,766
Total loans | 46,073 | 46,316
Consumer | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 351 | 486
Consumer | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 73 | 19
Consumer | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | 25 | 45
Foreign |  |
Financing receivable recorded investment |  |
Past due 90 days or Greater and Still Accruing | 144 | 739
Past due | 3,888 | 1,962
Loans, current | 140,701 | 148,555
Total loans | 144,589 | 150,517
Foreign | 30 to 59 Days |  |
Financing receivable recorded investment |  |
Past due | 3,018 | 1,106
Foreign | 60 to 89 Days |  |
Financing receivable recorded investment |  |
Past due | 726 | 117
Foreign | 90 Days or Greater |  |
Financing receivable recorded investment |  |
Past due | $ 144 | $ 739

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