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Allowance for Probable Loan Losses (Impaired Loans) (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2016 | Dec. 31, 2015
Interest Recognized |  |
Total trouble debt restructuring | $ 22,418 | $ 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 | $ 4,828 | 8,785
Total impaired loans with no related allowance | 42,577 | 51,663
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 5,981 | 9,233
Total impaired loans with no related allowance recorded | 74,677 | 64,788
Related Allowance | 961 | 2,206
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 5,821 | 5,694
Total impaired loans with no related allowance recorded | 40,450 | 53,575
Interest Recognized |  |
Total impaired loans with an allowance recorded |  | 92
Total impaired loans with no related allowance recorded | 547 | 441
Commercial |  |
Interest Recognized |  |
Total trouble debt restructuring | 10,710 | 2,419
Commercial | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance |  | 4,016
Total impaired loans with no related allowance | 21,412 | 26,930
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded |  | 4,156
Total impaired loans with no related allowance recorded | 50,737 | 38,845
Related Allowance |  | 1,704
Average recorded investment: |  |
Total impaired loans with an allowance recorded |  | 3,758
Total impaired loans with no related allowance recorded | 19,354 | 30,847
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 3 | 4
Commercial Real Estate: Other Construction and Land Development |  |
Interest Recognized |  |
Total trouble debt restructuring |  | 2,553
Commercial Real Estate: Other Construction and Land Development | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 1,958 | 167
Total impaired loans with no related allowance | 2,818 | 6,054
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 1,971 | 169
Total impaired loans with no related allowance recorded | 4,419 | 6,204
Related Allowance | 371 | 100
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 2,512 | 893
Total impaired loans with no related allowance recorded | 2,336 | 6,455
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 67 | 85
Commercial Real Estate: Farmland & Commercial |  |
Interest Recognized |  |
Total trouble debt restructuring | 3,086 | 2,853
Commercial Real Estate: Farmland & Commercial | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 2,808 | 4,003
Total impaired loans with no related allowance | 8,002 | 9,803
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 3,948 | 4,309
Total impaired loans with no related allowance recorded | 9,054 | 10,717
Related Allowance | 546 | 202
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 3,247 | 444
Total impaired loans with no related allowance recorded | 8,523 | 7,258
Interest Recognized |  |
Total impaired loans with an allowance recorded |  | 92
Total impaired loans with no related allowance recorded | 110 |
Commercial Real Estate: Multifamily | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance |  | 599
Total impaired loans with no related allowance | 552 | 178
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded |  | 599
Total impaired loans with no related allowance recorded | 562 | 178
Related Allowance |  | 200
Average recorded investment: |  |
Total impaired loans with an allowance recorded |  | 599
Total impaired loans with no related allowance recorded | 401 | 205
Residential First Lien |  |
Interest Recognized |  |
Total trouble debt restructuring | 6,181 | 5,316
Residential First Lien | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with related allowance | 62 |
Total impaired loans with no related allowance | 6,774 | 5,699
Unpaid principal balance: |  |
Total impaired loans with an allowance recorded | 62 |
Total impaired loans with no related allowance recorded | 6,847 | 5,822
Related Allowance | 44 |
Average recorded investment: |  |
Total impaired loans with an allowance recorded | 62 |
Total impaired loans with no related allowance recorded | 6,860 | 5,853
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 298 | 264
Residential Junior Lien |  |
Interest Recognized |  |
Total trouble debt restructuring | 812 | 929
Residential Junior Lien | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 978 | 950
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 1,017 | 972
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 1,011 | 1,182
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 52 | 68
Consumer |  |
Interest Recognized |  |
Total trouble debt restructuring | 1,269 | 1,263
Consumer | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 1,295 | 1,297
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 1,295 | 1,298
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 1,214 | 1,227
Interest Recognized |  |
Total impaired loans with no related allowance recorded | 1 | 3
Foreign |  |
Interest Recognized |  |
Total trouble debt restructuring | 360 | 386
Foreign | Class of Financing Receivable |  |
Recorded investment: |  |
Total impaired loans with no related allowance | 746 | 752
Unpaid principal balance: |  |
Total impaired loans with no related allowance recorded | 746 | 752
Average recorded investment: |  |
Total impaired loans with no related allowance recorded | 751 | 548
Interest Recognized |  |
Total impaired loans with no related allowance recorded | $ 16 | $ 17

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