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v3.20.1

FAIR VALUE, Significant Unobservable Inputs (Details) $ in Thousands | 3 Months Ended | 12 Months Ended
--- | --- | ---
Mar. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Impaired loans | $ 848 | $ 848
Other real estate owned | $ 1,469 | $ 1,270
Other real estate owned, Valuation Technique [Extensible List] | us-gaap:MarketApproachValuationTechniqueMember | us-gaap:MarketApproachValuationTechniqueMember
Other real estate owned, Measurement Input [Extensible List] | us-gaap:MeasurementInputCostToSellMember | us-gaap:MeasurementInputCostToSellMember
Mortgage servicing rights | $ 52 | $ 56
us-gaap_ValuationTechniqueDiscountedCashFlowMember | Weighted Average Constant Prepayment Rate [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Mortgage servicing rights, measurement input | 0.430 | 0.528
us-gaap_ValuationTechniqueDiscountedCashFlowMember | Weighted Average Discount Rate [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Mortgage servicing rights, measurement input | 0.0190 | 0.0300
us-gaap_ValuationTechniqueDiscountedCashFlowMember | Adequate Compensation [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Mortgage servicing rights, measurement input | 7 | 7
Minimum [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Impaired loans, measurement input | 0.090 | 0.090
Other real estate owned, measurement input | 0.090 | 0.090
Maximum [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Impaired loans, measurement input | 0.350 | 0.350
Other real estate owned, measurement input | 0.857 | 0.857
Weighted Average [Member] | Fair Value of Collateral [Member] | Estimated Cost of Disposal/Market Adjustment [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Impaired loans, measurement input | 0.279 | 0.279
Other real estate owned, measurement input | 0.355 | 0.371
Commitments to Originate Real Estate Loans for Sale [Member] |  |
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Commitments to originate real estate loans for sale | $ 530 |
Commitments to originate real estate loans for sale, Valuation Technique [Extensible List] | us-gaap:ValuationTechniqueDiscountedCashFlowMember |
Commitments to originate real estate loans for sale, Measurement Input [Extensible List] | cbu:MeasurementInputEmbeddedServicingValueMember |
Commitments to originate real estate loans for sale, measurement input | 0.01 |

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- Definition Carrying amount of other real estate not separately disclosed, including, but not limited to, real estate investments, real estate loans that qualify as investments in real estate, and premises that are no longer used in operations may also be included in real estate owned. This does not include real estate assets taken in settlement of troubled loans through surrender or foreclosure. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.10(4)) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 + Details
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