XML 77 R61.htm IDEA: XBRL DOCUMENT
v3.21.1

LOANS AND ALLOWANCE FOR LOAN LOSSES - Loan Portfolio (Details) - USD ($) $ in Thousands | Dec. 31, 2020 | Dec. 31, 2019
--- | --- | ---
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | $ 1,536,463 | $ 1,309,219
Interest receivable on loans | 5,035 | 3,684
Total recorded investment in loans | 1,541,498 | 1,312,903
Residential mortgages held for sale | 170 | 1,185
Commercial, and Agricultural |  |
Composition of loan portfolio [Abstract] |  |
Total recorded investment in loans | 370,252 | 230,922
Commercial mortgages |  |
Composition of loan portfolio [Abstract] |  |
Total recorded investment in loans | 719,145 | 650,570
Commercial mortgages | Construction |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 61,945 | 43,962
Total recorded investment in loans | 62,164 | 44,082
Commercial mortgages | Commercial mortgages |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 654,663 | 604,832
Total recorded investment in loans | 656,981 | 606,488
Residential Mortgages |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 239,401 | 188,338
Total recorded investment in loans | 240,013 | 188,874
Loans pledged as collateral | 101,900 | 170,000
Consumer Loans |  |
Composition of loan portfolio [Abstract] |  |
Total recorded investment in loans | 212,088 | 242,537
Consumer Loans | Home equity lines and loans |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 78,547 | 91,784
Total recorded investment in loans | 78,761 | 92,065
Consumer Loans | Indirect Consumer Loans |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 120,538 | 134,973
Total recorded investment in loans | 120,853 | 135,366
Consumer Loans | Direct consumer loans |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 12,423 | 15,038
Total recorded investment in loans | 12,474 | 15,106
Commercial and industrial |  |
Composition of loan portfolio [Abstract] |  |
Payroll Protection Program Loans - CARES Act | 150,900 |
Commercial and industrial | Commercial, and Agricultural |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 368,663 | 230,018
Total recorded investment in loans | 369,968 | 230,648
Agricultural | Commercial, and Agricultural |  |
Composition of loan portfolio [Abstract] |  |
Loans, net of deferred loan fees | 283 | 274
Total recorded investment in loans | $ 284 | $ 274

X
- Definition Financing Receivable, after Interest Receivable on Loans, before Allowance on Credit Loss + References No definition available. + Details
Name: | chmg_FinancingReceivableAfterInterestReceivableOnLoansBeforeAllowanceOnCreditLoss
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Financing Receivable, Payroll Protection Program Loans - CARES Act + References No definition available. + Details
Name: | chmg_FinancingReceivablePayrollProtectionProgramLoansCARESAct
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of interest earned but not received. Also called accrued interest or accrued interest receivable. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.8) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_InterestReceivable
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Carrying amount as of the balance sheet date of loans that have been pledged as collateral for borrowings. If the secured party has the right by contract or custom to sell or re-pledge the collateral, then the debtor reclassifies that asset and report that asset in its statement of financial position separately from other assets not so encumbered. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 50 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=118936363&loc=d3e5086-111524 + Details
Name: | us-gaap_LoansPledgedAsCollateral
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount, after allowance for bad debt, of loan receivables held-for-sale that are not part of a disposal group. Excludes loans and leases covered under loss sharing agreements and loans classified as debt securities. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=118952595&loc=d3e4428-111522 + Details
Name: | us-gaap_LoansReceivableHeldForSaleNetNotPartOfDisposalGroup
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 326 -SubTopic 20 -Section 50 -Paragraph 5 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=119407570&loc=SL82919230-210447 + Details
Name: | us-gaap_NotesReceivableGross
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Details
Name: | us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=chmg_CommercialMortgagesOtherLoansMember
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: |

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

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

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

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_CommercialAndIndustrialSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

X
- Details
Name: | us-gaap_EquitySecuritiesByIndustryAxis=us-gaap_AgriculturalSectorMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |