XML 58 R46.htm IDEA: XBRL DOCUMENT
v3.21.2

LOANS - Credit Quality By Past Due Status (Details) - USD ($) $ in Thousands | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Sep. 30, 2021 | Sep. 30, 2021 | Dec. 31, 2020
Aged analysis of the company's loans |  |  |
Total loans | $ 7,282,582 | $ 7,282,582 | $ 7,415,952
Interest income on nonaccrual loans | 0 | 0 |
Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 72,929
Total loans |  |  | 7,415,952
Total past due |  |  | 111,610
Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total loans |  |  | 34,759
Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 3,922
Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 7,304,342
Acquired Loans [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 65,967 | 65,967 |
Total loans | 7,282,582 | 7,282,582 |
Total past due | 93,056 | 93,056 |
Acquired Loans [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 25,215 | 25,215 |
Acquired Loans [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 1,874 | 1,874 |
Acquired Loans [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 7,189,526 | 7,189,526 |
Business Lending [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 3,092,177 | 3,092,177 | 3,440,077
Consumer Mortgage [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 2,470,974 | 2,470,974 | 2,401,499
Consumer Indirect [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 1,168,378 | 1,168,378 | 1,021,885
Consumer Direct [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 155,602 | 155,602 | 152,657
Home Equity [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 395,451 | 395,451 | 399,834
Commercial Portfolio Segment [Member] | Business Lending [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 47,820 | 47,820 |
Total loans | 3,092,177 | 3,092,177 | 3,440,077
Total past due | 53,077 | 53,077 |
Commercial Portfolio Segment [Member] | Business Lending [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 5,109 | 5,109 |
Commercial Portfolio Segment [Member] | Business Lending [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 148 | 148 |
Commercial Portfolio Segment [Member] | Business Lending [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 3,039,100 | 3,039,100 |
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 55,709
Total loans |  |  | 3,440,077
Total past due |  |  | 60,664
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 4,896
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 59
Commercial Portfolio Segment [Member] | Business Lending [Member] | Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 3,379,413
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 15,605 | 15,605 |
Total loans | 2,470,974 | 2,470,974 |
Total past due | 25,762 | 25,762 |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 8,869 | 8,869 |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 1,288 | 1,288 |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 2,445,212 | 2,445,212 |
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 14,970
Total loans |  |  | 2,401,499
Total past due |  |  | 31,257
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 13,236
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 3,051
Residential Portfolio Segment [Member] | Consumer Mortgage [Member] | Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 2,370,242
Consumer Portfolio Segment [Member] | Consumer Mortgage [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total loans | 2,470,974 | 2,470,974 | 2,401,499
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 0 | 0 |
Total loans | 1,168,378 | 1,168,378 | 1,021,885
Total past due | 8,769 | 8,769 |
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 8,638 | 8,638 |
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 131 | 131 |
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 1,159,609 | 1,159,609 |
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 1
Total loans |  |  | 1,021,885
Total past due |  |  | 13,381
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 13,161
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 219
Consumer Portfolio Segment [Member] | Consumer Indirect [Member] | Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 1,008,504
Consumer Portfolio Segment [Member] | Consumer Direct [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 1 | 1 |
Total loans | 155,602 | 155,602 | 152,657
Total past due | 628 | 628 |
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 608 | 608 |
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 19 | 19 |
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 154,974 | 154,974 |
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 3
Total loans |  |  | 152,657
Total past due |  |  | 1,201
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 1,170
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 28
Consumer Portfolio Segment [Member] | Consumer Direct [Member] | Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 151,456
Consumer Portfolio Segment [Member] | Home Equity [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual | 2,541 | 2,541 |
Total loans | 395,451 | 395,451 | 399,834
Total past due | 4,820 | 4,820 |
Consumer Portfolio Segment [Member] | Home Equity [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 1,991 | 1,991 |
Consumer Portfolio Segment [Member] | Home Equity [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | 288 | 288 |
Consumer Portfolio Segment [Member] | Home Equity [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due | $ 390,631 | $ 390,631 |
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loan [Member] |  |  |
Aged analysis of the company's loans |  |  |
Nonaccrual |  |  | 2,246
Total loans |  |  | 399,834
Total past due |  |  | 5,107
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loan [Member] | Past Due 30 - 89 Days [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 2,296
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loan [Member] | Financial Asset, Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | 565
Consumer Portfolio Segment [Member] | Home Equity [Member] | Legacy Loan [Member] | Financial Asset, Not Past Due [Member] |  |  |
Aged analysis of the company's loans |  |  |
Total past due |  |  | $ 394,727

X
- Definition Amount of interest income on financing receivable on nonaccrual status. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 + Details
Name: | us-gaap_FinancingReceivableNonaccrualInterestIncome
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | duration

X
- Definition Amount of financing receivable on nonaccrual status. + 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=123577603&loc=d3e5111-111524 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 16 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919258-210447 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (3) Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (2) + Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentNonaccrualStatus
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount before allowance of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans and leases covered under loss sharing agreements. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=124259787&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansAndLeasesReceivableGrossCarryingAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, before allowance for credit loss, of financing receivable. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 7A -URI http://asc.fasb.org/extlink&oid=123577603&loc=SL6953401-111524 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 79 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922352-210448 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 14 -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919253-210447 Reference 4: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=124255206&loc=SL82895884-210446 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=124255953&loc=SL82919230-210447 Reference 6: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 326 -SubTopic 20 -Section 55 -Paragraph 80 -URI http://asc.fasb.org/extlink&oid=124267575&loc=SL82922355-210448 Reference 7: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (1) Reference 8: http://www.xbrl.org/2003/role/disclosureRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1405 -Paragraph (a) -Subparagraph (2) Reference 9: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher SEC -Name Regulation S-K (SK) -Number 229 -Section 1404 -Paragraph (a) + Details
Name: | us-gaap_NotesReceivableGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=cbu_LegacyLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=cbu_FinancingReceivables30To89DaysPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablesPeriodPastDueAxis=us-gaap_FinancialAssetNotPastDueMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_AccountsNotesLoansAndFinancingReceivableByReceivableTypeAxis=cbu_AcquiredLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_CommercialLoanMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialMortgageMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cbu_ConsumerInstallmentIndirectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cbu_ConsumerInstallmentDirectMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cbu_HomeEquityReceivablesMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_CommercialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ResidentialPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_FinancingReceivablePortfolioSegmentAxis=us-gaap_ConsumerPortfolioSegmentMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |