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LOANS AND ALLOWANCE FOR LOAN LOSSES - Narrative (Details) - USD ($) | 9 Months Ended |
--- | --- | ---
Sep. 30, 2022 | Dec. 31, 2021
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Allowance for loan losses | $ 0 | $ 0
Number of days past due after which a retail loan is rated | 90 days |
Commercial and industrial |  |
Accounts, Notes, Loans and Financing Receivable [Line Items] |  |
Payroll protection program loans | $ 1,400,000 | $ 43,200,000

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- Definition Financing Receivable, Allowance for Loan Losses in Payroll Protection Program Loans + References No definition available. + Details
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- Definition Financing Receivable, Payroll Protection Program Loans - CARES Act + References No definition available. + Details
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Namespace Prefix: | chmg_
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- Definition Number Of Days Past Due After Which A Loan Will Be Rated + References No definition available. + Details
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- Details
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