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v3.20.2

FAIR VALUE - Significant Unobservable Inputs (Details) $ in Thousands | 9 Months Ended | 12 Months Ended
--- | --- | ---
Sep. 30, 2020 USD ($) | Dec. 31, 2019 USD ($)
Significant Unobservable Inputs used in determination of Fair Value of Assets Classified as Level 3 [Abstract] |  |
Impaired loans | $ 6,808 | $ 848
Other real estate owned | $ 1,209 | $ 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 | $ 460 | $ 56
Discounted Cash Flow [Member] | 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 |  | 0.528
Discounted Cash Flow [Member] | 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 |  | 0.0300
Discounted Cash Flow [Member] | 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 | 0.152 | 0.090
Minimum [Member] | Discounted Cash Flow [Member] | 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 | 0.138 |
Minimum [Member] | Discounted Cash Flow [Member] | 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 | 0.0122 |
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 | 0.787 | 0.350
Other real estate owned, measurement input | 0.535 | 0.857
Maximum [Member] | Discounted Cash Flow [Member] | 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 | 0.147 |
Maximum [Member] | Discounted Cash Flow [Member] | 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 | 0.0198 |
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 | 0.588 | 0.279
Other real estate owned, measurement input | 0.313 | 0.371
Weighted Average [Member] | Discounted Cash Flow [Member] | 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 | 0.146 |
Weighted Average [Member] | Discounted Cash Flow [Member] | 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 | 0.0192 |
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 | $ 2,684 |
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 | 0.010 |

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- Definition Fair value, after the effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=121572278&loc=d3e13433-108611 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
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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=120398452&loc=d3e534808-122878 + Details
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- Definition Fair value of contract to service financial assets under which the benefits of servicing are expected to more than adequately compensate the servicer. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 50 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=116651436&loc=d3e122739-111746 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 20 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7516967&loc=d3e66267-113978 + Details
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