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PARENT COMPANY FINANCIAL INFORMATION - STATEMENTS OF INCOME (Details) - USD ($) $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2021 | Dec. 31, 2020
STATEMENTS OF INCOME [Abstract] |  |
Income before income tax expense | $ 33,760 | $ 23,869
Income tax benefit | 7,335 | 4,607
Net income | 26,425 | 19,262
Parent Company |  |
STATEMENTS OF INCOME [Abstract] |  |
Dividends from subsidiary bank and non-bank | 6,854 | 10,806
Interest and dividend income | 4 | 5
Non-interest income | 85 | (50)
Non-interest expenses | 432 | 503
Income before impact of subsidiaries' undistributed earnings | 6,511 | 10,258
Income before income tax expense | 26,299 | 19,080
Income tax benefit | (126) | (182)
Net income | 26,425 | 19,262
Parent Company | Chemung Canal Trust Company |  |
STATEMENTS OF INCOME [Abstract] |  |
Income (loss) from equity method investments | 19,492 | 8,204
Parent Company | CFS Group Inc. |  |
STATEMENTS OF INCOME [Abstract] |  |
Income (loss) from equity method investments | 198 | 8
Parent Company | Chemung Risk Management |  |
STATEMENTS OF INCOME [Abstract] |  |
Income (loss) from equity method investments | $ 98 | $ 610

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