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Allowance for Probable Loan Losses (Impaired Loans) (Details) - USD ($) $ in Thousands | 3 Months Ended | 6 Months Ended | 12 Months Ended
--- | --- | --- | ---
Jun. 30, 2016 | Jun. 30, 2015 | Jun. 30, 2016 | Jun. 30, 2015 | Dec. 31, 2015
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | $ 15,420 |  | $ 15,420 |  | $ 15,719
Period of charge off for past due unsecured commercial loans |  |  | 90 days |  |
Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 7,549 |  | $ 7,549 |  | 8,785
Total impaired loans with no related allowance | 30,174 |  | 30,174 |  | 51,663
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 10,017 |  | 10,017 |  | 9,233
Total impaired loans with no related allowance recorded | 58,271 |  | 58,271 |  | 64,788
Related Allowance | 1,078 |  | 1,078 |  | 2,206
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 9,376 | $ 22,306 | 9,839 | $ 27,126 | 33,286
Total impaired loans with no related allowance recorded | 31,509 | 39,723 | 38,093 | 40,606 | 42,643
Interest Recognized |  |  |  |  |
Total impaired loans with an allowance recorded | 22 | 23 | 48 | 46 | 92
Total impaired loans with no related allowance recorded | 112 | 105 | 228 | 212 | 106
Commercial |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 2,407 |  | 2,407 |  | 2,419
Commercial | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 2,319 |  | 2,319 |  | 4,016
Total impaired loans with no related allowance | 10,832 |  | 10,832 |  | 26,930
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 3,660 |  | 3,660 |  | 4,156
Total impaired loans with no related allowance recorded | 37,838 |  | 37,838 |  | 38,845
Related Allowance | 831 |  | 831 |  | 1,704
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 3,453 | 15,121 | 3,735 | 17,828 | 19,313
Total impaired loans with no related allowance recorded | 10,837 | 20,752 | 15,944 | 20,288 | 21,291
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 1 | 1 | 2 | 2 | 1
Commercial Real Estate: Other Construction and Land Development |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 1,879 |  | 1,879 |  | 2,553
Commercial Real Estate: Other Construction and Land Development | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 161 |  | 161 |  | 167
Total impaired loans with no related allowance | 3,989 |  | 3,989 |  | 6,054
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 169 |  | 169 |  | 169
Total impaired loans with no related allowance recorded | 3,995 |  | 3,995 |  | 6,204
Related Allowance | 116 |  | 116 |  | 100
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 162 | 3,652 | 163 | 4,988 | 7,183
Total impaired loans with no related allowance recorded | 5,155 | 3,291 | 5,726 | 3,451 | 6,045
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 20 | 19 | 45 | 37 | 20
Commercial Real Estate: Farmland & Commercial |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 2,830 |  | 2,830 |  | 2,853
Commercial Real Estate: Farmland & Commercial | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance | 5,069 |  | 5,069 |  | 4,003
Total impaired loans with no related allowance | 5,174 |  | 5,174 |  | 9,803
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded | 6,188 |  | 6,188 |  | 4,309
Total impaired loans with no related allowance recorded | 6,144 |  | 6,144 |  | 10,717
Related Allowance | 131 |  | 131 |  | 202
Average recorded investment: |  |  |  |  |
Total impaired loans with an allowance recorded | 5,761 | 3,533 | 5,941 | 4,310 | 6,790
Total impaired loans with no related allowance recorded | 5,709 | 6,688 | 6,649 | 7,778 | 6,203
Interest Recognized |  |  |  |  |
Total impaired loans with an allowance recorded | 22 | 23 | 48 | 46 | 92
Commercial Real Estate: Multifamily | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with related allowance |  |  |  |  | 599
Total impaired loans with no related allowance | 590 |  | 590 |  | 178
Unpaid principal balance: |  |  |  |  |
Total impaired loans with an allowance recorded |  |  |  |  | 599
Total impaired loans with no related allowance recorded | 591 |  | 591 |  | 178
Related Allowance |  |  |  |  | 200
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 301 | 832 | 235 | 839 | 819
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded |  |  |  | 1 |
Residential First Lien |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 5,960 |  | 5,960 |  | 5,316
Residential First Lien | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 6,683 |  | 6,683 |  | 5,699
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 6,758 |  | 6,758 |  | 5,822
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 6,610 | 5,289 | 6,594 | 5,329 | 5,315
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 74 | 61 | 145 | 123 | 65
Residential Junior Lien |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 839 |  | 839 |  | 929
Residential Junior Lien | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 1,021 |  | 1,021 |  | 950
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,059 |  | 1,059 |  | 972
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,008 | 1,317 | 1,022 | 1,346 | 1,075
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 12 | 19 | 27 | 39 | 15
Consumer |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 1,132 |  | 1,132 |  | 1,263
Consumer | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 1,132 |  | 1,132 |  | 1,297
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,133 |  | 1,133 |  | 1,298
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 1,134 | 1,153 | 1,172 | 1,171 | 1,263
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | 1 | 1 | 1 | 1 | 1
Foreign |  |  |  |  |
Interest Recognized |  |  |  |  |
Total trouble debt restructuring | 373 |  | 373 |  | 386
Foreign | Class of Financing Receivable |  |  |  |  |
Recorded investment: |  |  |  |  |
Total impaired loans with no related allowance | 753 |  | 753 |  | 752
Unpaid principal balance: |  |  |  |  |
Total impaired loans with no related allowance recorded | 753 |  | 753 |  | 752
Average recorded investment: |  |  |  |  |
Total impaired loans with no related allowance recorded | 755 | 401 | 751 | 404 | 632
Interest Recognized |  |  |  |  |
Total impaired loans with no related allowance recorded | $ 4 | $ 4 | $ 8 | $ 9 | $ 4

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