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Allowance for Probable Loan Losses (Non-accrual Basis By Loan Class) (Details) - USD ($) $ in Thousands | Sep. 30, 2018 | Dec. 31, 2017
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Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | $ 24,300 | $ 54,730
Commercial |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | 17,199 | 17,909
Commercial Real Estate:Other Construction and Land Development |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | 2,130 | 2,455
Commercial Real Estate: Farmland and Commercial |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | 4,157 | 33,123
Commercial Real Estate: Multifamily |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | 586 | 476
Residential First Lien |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | 197 | 712
Residential Junior Lien |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total |  | 11
Consumer |  |
Loan loss allowances, financing receivable past due |  |
Non-accrual loans, total | $ 31 | $ 44

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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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