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Allowance for Probable Loan Losses (Non-accrual Basis By Loan Class) (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2018 | Dec. 31, 2017 | Dec. 31, 2016
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | $ 15,791,000 | $ 54,730,000 | $ 37,245,000
Reduced interest income on non-accrual loans | 1,119,000 | 977,000 | $ 2,461,000
Commercial |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 9,143,000 | 17,909,000 |
Commercial Real Estate:Other Construction and Land Development |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 2,092,000 | 2,455,000 |
Commercial Real Estate: Farmland and Commercial |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 3,509,000 | 33,123,000 |
Commercial Real Estate: Multifamily |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 507,000 | 476,000 |
Residential First Lien |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 347,000 | 712,000 |
Residential Junior Lien |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | 171,000 | 11,000 |
Consumer |  |  |
Loan loss allowances, financing receivable past due |  |  |
Non-accrual loans, total | $ 22,000 | $ 44,000 |

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- Definition Represents the reduction in interest income on recorded investment in financing receivables that are on nonaccrual status. + References No definition available. + Details
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- Definition Recorded investment in financing receivables that are on nonaccrual status as of the balance sheet date. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84173941&loc=d3e5111-111524 + Details
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