FAIR VALUE - Carrying Amounts and Estimated Fair Values of Other Financial Instruments (Details) - USD ($) $ in Thousands	Sep. 30, 2025	Dec. 31, 2024
Financial assets:
Cash and due from financial institutions	$ 32,445	$ 26,224
Interest-earning deposits in other financial institutions	75,201	20,811
Loans, net and loans held for sale	2,178,711	2,050,031
Derivative assets	17,966	23,829
Deposits:
FHLBNY advances	0	109,110
Subordinated debt, net of deferred issuance costs	44,002	0
Derivative liabilities	18,056	23,851
Recurring
Financial assets:
Securities available for sale	280,514	531,442
Derivative assets	17,966	23,829
Deposits:
Derivative liabilities	18,056	23,851
Recurring \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Securities available for sale	0	56,906
Derivative assets	0	0
Deposits:
Derivative liabilities	0	0
Recurring \| Significant Other Observable Inputs (Level 2)
Financial assets:
Securities available for sale	274,445	462,404
Derivative assets	17,966	23,829
Deposits:
Derivative liabilities	18,056	23,851
Recurring \| Significant Unobservable Inputs (Level 3)
Financial assets:
Securities available for sale	6,069	12,132
Derivative assets	0	0
Deposits:
Derivative liabilities	0	0
Recurring \| Carrying Amount
Financial assets:
Cash and due from financial institutions	32,445	26,224
Interest-earning deposits in other financial institutions	75,201	20,811
Equity investments	3,616	3,235
Securities available for sale	280,514	531,442
Securities held to maturity	680	808
FHLBNY and FRBNY stock	5,524	9,117
Loans, net and loans held for sale	2,205,431	2,071,419
Derivative assets	17,966	23,829
Deposits:
Demand, savings, and insured money market deposits	1,873,681	1,772,971
Time deposits	484,835	623,912
FHLBNY advances		109,110
Subordinated debt, net of deferred issuance costs	44,002
Derivative liabilities	18,056	23,851
Recurring \| Estimated Fair Value
Financial assets:
Cash and due from financial institutions	32,445	26,224
Interest-earning deposits in other financial institutions	75,201	20,811
Equity investments	3,616	3,235
Securities available for sale	280,514	531,442
Securities held to maturity	680	808
Loans, net and loans held for sale	2,134,472	1,981,851
Derivative assets	17,966	23,829
Deposits:
Demand, savings, and insured money market deposits	1,873,681	1,772,971
Time deposits	485,423	622,920
FHLBNY advances		109,083
Subordinated debt, net of deferred issuance costs	46,286
Derivative liabilities	18,056	23,851
Recurring \| Estimated Fair Value \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Financial assets:
Cash and due from financial institutions	32,445	26,224
Interest-earning deposits in other financial institutions	75,201	20,811
Equity investments	3,616	3,235
Securities available for sale	0	56,906
Securities held to maturity	0	0
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	0	0
Derivative assets	0	0
Deposits:
Demand, savings, and insured money market deposits	1,873,681	1,772,971
Time deposits	0	0
FHLBNY advances		0
Subordinated debt, net of deferred issuance costs	0
Derivative liabilities	0	0
Recurring \| Estimated Fair Value \| Significant Other Observable Inputs (Level 2)
Financial assets:
Cash and due from financial institutions	0	0
Interest-earning deposits in other financial institutions	0	0
Equity investments	0	0
Securities available for sale	274,445	462,404
Securities held to maturity	0	0
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	0	0
Derivative assets	17,966	23,829
Deposits:
Demand, savings, and insured money market deposits	0	0
Time deposits	485,423	622,920
FHLBNY advances		109,083
Subordinated debt, net of deferred issuance costs	46,286
Derivative liabilities	18,056	23,851
Recurring \| Estimated Fair Value \| Significant Unobservable Inputs (Level 3)
Financial assets:
Cash and due from financial institutions	0	0
Interest-earning deposits in other financial institutions	0	0
Equity investments	0	0
Securities available for sale	6,069	12,132
Securities held to maturity	680	808
FHLBNY and FRBNY stock	0	0
Loans, net and loans held for sale	2,134,472	1,981,851
Derivative assets	0	0
Deposits:
Demand, savings, and insured money market deposits	0	0
Time deposits	0	0
FHLBNY advances		0
Subordinated debt, net of deferred issuance costs	0
Derivative liabilities	$ 0	$ 0

CHEMUNG FINANCIAL CORP 10-Q