XML 124 R109.htm IDEA: XBRL DOCUMENT
v3.22.4

FAIR VALUE - Financial assets and liabilities accounted for at fair value on a recurring basis (Details) - USD ($) $ in Thousands | Dec. 31, 2022 | Dec. 31, 2021
--- | --- | ---
Available-for-sale investment securities |  |
Available-for-sale investment securities | $ 4,151,851 | $ 4,934,210
Equity securities | 419 | 463
U.S. Treasury and agency securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 3,243,537 | 3,998,564
Obligations of state and political subdivisions |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 504,297 | 430,289
Government agency mortgage-backed securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 384,633 | 477,056
Corporate debt securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 7,114 | 7,962
Government agency collateralized mortgage obligations |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 12,270 | 20,339
Level 3 | Commitments to originate real estate loans for sale |  |
Available-for-sale investment securities |  |
Derivative asset | 5 | 51
Recurring |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 4,151,851 | 4,934,210
Equity securities | 419 | 463
Total | 4,152,280 | 4,935,049
Recurring | Interest rate swap agreements |  |
Available-for-sale investment securities |  |
Derivative asset | 1 | 296
Derivative liability | (1) | (3)
Recurring | Forward sales commitments |  |
Available-for-sale investment securities |  |
Derivative asset |  | 32
Derivative liability | 5 |
Recurring | Commitments to originate real estate loans for sale |  |
Available-for-sale investment securities |  |
Derivative asset | 5 | 51
Recurring | U.S. Treasury and agency securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 3,243,537 | 3,998,564
Recurring | Obligations of state and political subdivisions |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 504,297 | 430,289
Recurring | Government agency mortgage-backed securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 384,633 | 477,056
Recurring | Corporate debt securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 7,114 | 7,962
Recurring | Government agency collateralized mortgage obligations |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 12,270 | 20,339
Recurring | Level 1 |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 3,178,189 | 3,900,924
Equity securities | 419 | 463
Total | 3,178,608 | 3,901,387
Recurring | Level 1 | Interest rate swap agreements |  |
Available-for-sale investment securities |  |
Derivative asset | 0 | 0
Derivative liability | 0 | 0
Recurring | Level 1 | Forward sales commitments |  |
Available-for-sale investment securities |  |
Derivative asset |  | 0
Derivative liability | 0 |
Recurring | Level 1 | Commitments to originate real estate loans for sale |  |
Available-for-sale investment securities |  |
Derivative asset | 0 | 0
Recurring | Level 1 | U.S. Treasury and agency securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 3,178,189 | 3,900,924
Recurring | Level 1 | Obligations of state and political subdivisions |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 1 | Government agency mortgage-backed securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 1 | Corporate debt securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 1 | Government agency collateralized mortgage obligations |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 2 |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 973,662 | 1,033,286
Equity securities | 0 | 0
Total | 973,667 | 1,033,611
Recurring | Level 2 | Interest rate swap agreements |  |
Available-for-sale investment securities |  |
Derivative asset | 1 | 296
Derivative liability | (1) | (3)
Recurring | Level 2 | Forward sales commitments |  |
Available-for-sale investment securities |  |
Derivative asset |  | 32
Derivative liability | 5 |
Recurring | Level 2 | Commitments to originate real estate loans for sale |  |
Available-for-sale investment securities |  |
Derivative asset | 0 | 0
Recurring | Level 2 | U.S. Treasury and agency securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 65,348 | 97,640
Recurring | Level 2 | Obligations of state and political subdivisions |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 504,297 | 430,289
Recurring | Level 2 | Government agency mortgage-backed securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 384,633 | 477,056
Recurring | Level 2 | Corporate debt securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 7,114 | 7,962
Recurring | Level 2 | Government agency collateralized mortgage obligations |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 12,270 | 20,339
Recurring | Level 3 |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Equity securities | 0 | 0
Total | 5 | 51
Recurring | Level 3 | Interest rate swap agreements |  |
Available-for-sale investment securities |  |
Derivative asset | 0 | 0
Derivative liability | 0 | 0
Recurring | Level 3 | Forward sales commitments |  |
Available-for-sale investment securities |  |
Derivative asset |  | 0
Derivative liability | 0 |
Recurring | Level 3 | Commitments to originate real estate loans for sale |  |
Available-for-sale investment securities |  |
Derivative asset | 5 | 51
Recurring | Level 3 | U.S. Treasury and agency securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 3 | Obligations of state and political subdivisions |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 3 | Government agency mortgage-backed securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 3 | Corporate debt securities |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | 0 | 0
Recurring | Level 3 | Government agency collateralized mortgage obligations |  |
Available-for-sale investment securities |  |
Available-for-sale investment securities | $ 0 | $ 0

X
- References No definition available. + Details
Name: | us-gaap_AvailableForSaleSecuritiesAbstract
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03(6)) -URI https://asc.fasb.org/extlink&oid=126897435&loc=d3e534808-122878 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 30 -Section 45 -Paragraph 1 -URI https://asc.fasb.org/extlink&oid=124258926&loc=SL82898722-210454 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (b) -URI https://asc.fasb.org/extlink&oid=124260329&loc=d3e26610-111562 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (aa) -URI https://asc.fasb.org/extlink&oid=126970911&loc=d3e27161-111563 + Details
Name: | us-gaap_AvailableForSaleSecuritiesDebtSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- 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://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 + Details
Name: | us-gaap_DerivativeAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value, after the effects of master netting arrangements, of a financial liability or 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 liabilities not subject to a master netting arrangement and not elected to be offset. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226008-175313 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -URI https://asc.fasb.org/extlink&oid=123594938&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 22 -URI https://asc.fasb.org/extlink&oid=99393222&loc=SL20226052-175313 + Details
Name: | us-gaap_DerivativeLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of investment in equity security measured at fair value with change in fair value recognized in net income (FV-NI), classified as current. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(2)) -URI https://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section 45 -Paragraph 1 -Subparagraph (f) -URI https://asc.fasb.org/extlink&oid=124098289&loc=d3e6676-107765 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 45 -Paragraph 1A -URI https://asc.fasb.org/extlink&oid=123594786&loc=SL75136599-209740 + Details
Name: | us-gaap_EquitySecuritiesFvNi
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of asset after deduction of liability. + References No definition available. + Details
Name: | us-gaap_FairValueNetAssetLiability
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USTreasuryAndGovernmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_USStatesAndPoliticalSubdivisionsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_MortgageBackedSecuritiesIssuedByUSGovernmentSponsoredEnterprisesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=us-gaap_CorporateDebtSecuritiesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancialInstrumentAxis=cbu_GovernmentAgencyCollateralizedMortgageObligationsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel3Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_LoanOriginationCommitmentsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_InterestRateSwapMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_DerivativeInstrumentRiskAxis=us-gaap_ForwardContractsMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel1Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FairValueByFairValueHierarchyLevelAxis=us-gaap_FairValueInputsLevel2Member
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |