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PARENT COMPANY FINANCIAL INFORMATION - STATEMENTS OF INCOME (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2023 | Dec. 31, 2022
STATEMENTS OF INCOME [Abstract] |  |
Income before income tax expense | $ 31,501 | $ 36,889
Income tax benefit | 6,501 | 8,106
Net income | 25,000 | 28,783
Parent Company |  |
STATEMENTS OF INCOME [Abstract] |  |
Dividends from subsidiary bank and non-bank | 7,204 | 7,051
Interest and dividend income | 11 | 7
Non-interest income | (125) | 10
Non-interest expenses | 345 | 586
Income before impact of subsidiaries' undistributed earnings | 6,745 | 6,482
Income before income tax expense | 24,835 | 28,590
Income tax benefit | (165) | (193)
Net income | 25,000 | 28,783
Parent Company | Chemung Canal Trust Company |  |
STATEMENTS OF INCOME [Abstract] |  |
Income (loss) from equity method investments | 18,267 | 21,638
Parent Company | CFS Group Inc. |  |
STATEMENTS OF INCOME [Abstract] |  |
Income (loss) from equity method investments | 124 | 220
Parent Company | Chemung Risk Management |  |
STATEMENTS OF INCOME [Abstract] |  |
Distributed earnings of Chemung Risk Management, Inc. | $ (301) | $ 250

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