XML 55 R43.htm IDEA: XBRL DOCUMENT
v3.7.0.1

FAIR VALUE (Details) - USD ($) $ in Thousands | Mar. 31, 2017 | Dec. 31, 2016 | Oct. 31, 2016
--- | --- | --- | ---
Financial Assets [Abstract] |  |  |
Total available for sale securities | $ 302,581 | $ 303,402 |
Trading assets | 826 | 774 |
Transfers from Level 2 to Level 1 |  | 103 | $ 158
Recurring |  |  |
Financial Assets [Abstract] |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 17,440 | 17,455 |
Mortgage-backed securities, residential | 239,678 | 245,866 |
Obligations of states and political subdivisions | 44,155 | 38,740 |
Corporate bonds and notes | 251 | 250 |
SBA loan pools | 550 | 570 |
Corporate stocks | 507 | 521 |
Total available for sale securities | 302,581 | 303,402 |
Trading assets | 826 | 774 |
Derivative assets | 747 | 693 |
Derivative liabilities | 812 | 761 |
Recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Financial Assets [Abstract] |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 0 | 0 |
Mortgage-backed securities, residential | 0 | 0 |
Obligations of states and political subdivisions | 0 | 0 |
Corporate bonds and notes | 0 | 0 |
SBA loan pools | 0 | 0 |
Corporate stocks | 175 | 170 |
Total available for sale securities | 175 | 170 |
Trading assets | 826 | 774 |
Derivative assets | 0 | 0 |
Derivative liabilities | 0 | 0 |
Recurring | Significant Other Observable Inputs (Level 2) |  |  |
Financial Assets [Abstract] |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 17,440 | 17,455 |
Mortgage-backed securities, residential | 239,678 | 245,866 |
Obligations of states and political subdivisions | 44,155 | 38,740 |
Corporate bonds and notes | 0 | 0 |
SBA loan pools | 550 | 570 |
Corporate stocks | 332 | 351 |
Total available for sale securities | 302,155 | 302,982 |
Trading assets | 0 | 0 |
Derivative assets | 747 | 693 |
Derivative liabilities | 747 | 693 |
Recurring | Significant Unobservable Inputs (Level 3) |  |  |
Financial Assets [Abstract] |  |  |
Obligations of U.S. Government and U.S. Government sponsored enterprises | 0 | 0 |
Mortgage-backed securities, residential | 0 | 0 |
Obligations of states and political subdivisions | 0 | 0 |
Corporate bonds and notes | 251 | 250 |
SBA loan pools | 0 | 0 |
Corporate stocks | 0 | 0 |
Total available for sale securities | 251 | 250 |
Trading assets | 0 | 0 |
Derivative assets | 0 | 0 |
Derivative liabilities | 65 | 68 |
Impaired Loans: | Non-recurring |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 3,344 | 2,850 |
Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 0 | 0 |
Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 0 | 0 |
Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 3,344 | 2,850 |
Other real estate owned: | Non-recurring |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 255 | 344 |
Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 0 | 0 |
Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 0 | 0 |
Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 255 | 344 |
Commercial mortgages | Impaired Loans: | Non-recurring |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 3,344 | 2,631 |
Commercial mortgages | Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 0 | 0 |
Commercial mortgages | Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 0 | 0 |
Commercial mortgages | Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans | 3,344 | 2,631 |
Home equity lines and loans | Impaired Loans: | Non-recurring |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans |  | 219 |
Home equity lines and loans | Impaired Loans: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans |  | 0 |
Home equity lines and loans | Impaired Loans: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans |  | 0 |
Home equity lines and loans | Impaired Loans: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total impaired loans |  | 219 |
Residential mortgages | Other real estate owned: | Non-recurring |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 255 | 344 |
Residential mortgages | Other real estate owned: | Non-recurring | Quoted Prices in Active Markets for Identical Assets (Level 1) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 0 | 0 |
Residential mortgages | Other real estate owned: | Non-recurring | Significant Other Observable Inputs (Level 2) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | 0 | 0 |
Residential mortgages | Other real estate owned: | Non-recurring | Significant Unobservable Inputs (Level 3) |  |  |
Impaired Loans, Fair Value Disclosure [Abstract] |  |  |
Total other real estate owned, net | $ 255 | $ 344 |

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents corporate bonds and notes as of the balance sheet date which have been categorized as available-for-sale. + References No definition available. + Details
Name: | chmg_CorporateBondsAndNotesFairValueDisclosure
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents corporate stocks as of the balance sheet date which have been categorized as available-for-sale. + References No definition available. + Details
Name: | chmg_CorporateStocksFairValueDisclosure
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents obligations of states and political subdivisions as of the balance sheet date which have been categorized as available-for-sale. + References No definition available. + Details
Name: | chmg_ObligationsOfStatesAndPoliticalSubdivisionsFairValueDisclosure
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents investments in Obligations of U.S. Government and U.S. Government sponsored enterprises as of the balance sheet date which have been categorized as available-for-sale. + References No definition available. + Details
Name: | chmg_ObligationsOfUSGovernmentAndUSGovernmentSponsoredEnterprisesFairValueDisclosure
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition This element represents the portion of the balance sheet assertion valued at fair value by the entity whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission. This item represents small business administration pool loans as of the balance sheet date which have been categorized as available-for-sale. + References No definition available. + Details
Name: | chmg_SmallBusinessAdministrationPoolLoansFairValueDisclosure
Namespace Prefix: | chmg_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

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

X
- Definition Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 25 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=65884222&loc=d3e22054-111558 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 50 -Paragraph 5 -Subparagraph (aa) -URI http://asc.fasb.org/extlink&oid=73527792&loc=d3e27232-111563 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562 + Details
Name: | us-gaap_AvailableForSaleSecurities
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/presentationRef -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 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313 + 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/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 55 -Paragraph 10 -URI http://asc.fasb.org/extlink&oid=51825145&loc=SL20226008-175313 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 15 -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13495-108611 Reference 3: http://www.xbrl.org/2003/role/presentationRef -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 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 825 -SubTopic 10 -Section 50 -Paragraph 10 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=73719730&loc=d3e13433-108611 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41271-113958 Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 45 -Paragraph 5 -URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41228-113958 + Details
Name: | us-gaap_DerivativeLiabilities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=66048111&loc=d3e19207-110258 + Details
Name: | us-gaap_FairValueAssetsLevel2ToLevel1TransfersAmount
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 310 -SubTopic 10 -Glossary Loan -URI http://asc.fasb.org/extlink&oid=6517073 + Details
Name: | us-gaap_LoansReceivableFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Fair value of securitized, pay-through debt securities collateralized by real estate mortgage loans classified as available-for-sale. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Mortgage-Backed Securities -URI http://asc.fasb.org/extlink&oid=6517959 + Details
Name: | us-gaap_MortgageBackedSecuritiesAvailableForSaleFairValueDisclosure
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Carrying amount as of the balance sheet date of other real estate and foreclosed assets. Other real estate may include 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. Foreclosed assets include all assets obtained in full or partial satisfaction of a debt arrangement through foreclosure proceedings. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -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
Name: | us-gaap_OtherRealEstateAndForeclosedAssets
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Definition Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26626-111562 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 942 -SubTopic 210 -Section S99 -Paragraph 1 -Subparagraph (SX 210.9-03.4) -URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 320 -SubTopic 10 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66010992&loc=d3e26610-111562 Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Trading Securities -URI http://asc.fasb.org/extlink&oid=6526789 + Details
Name: | us-gaap_TradingSecurities
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | debit
Period Type: | instant

X
- Details
Name: | us-gaap_FairValueByMeasurementFrequencyAxis=us-gaap_FairValueMeasurementsRecurringMember
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: |

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

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=chmg_ImpairedLoansMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

X
- Details
Name: | us-gaap_FairValueByAssetClassAxis=chmg_OtherRealEstateOwnedMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |

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

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