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SUMMARY OF SIGNIFICANT ACCOUNTING POLICIES - Additional Information (Details) | 12 Months Ended |
--- | --- | ---
Dec. 31, 2017 USD ($) segment | Dec. 31, 2016 USD ($)
Property, Plant and Equipment [Line Items] |  |
Period of delinquency after which a loan is placed on non-accrual status | 90 days |
Number of consecutive months for which loans remain current before non-accrual loans are returned to accrual status | 6 months |
Rolling historical period of net losses used in evaluating general component of valuation allowance for loans not impaired but classified as substandard and special mention | 5 years |
Number of most recent years of actual loss history used in determining historical loss experience for all other unclassified loans | 2 years |
Assets under management | $ 1,952,000,000 | $ 1,721,000,000
Cash or securities pledged as collateral | $ 231,600,000 | 191,000,000
Number of operating segments | segment | 2 |
Buildings | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful lives | 15 years |
Buildings | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful lives | 50 years |
Equipment and Furniture | Minimum |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful lives | 3 years |
Equipment and Furniture | Maximum |  |
Property, Plant and Equipment [Line Items] |  |
Estimated useful lives | 10 years |
Chemung Financial Corporation |  |
Property, Plant and Equipment [Line Items] |  |
Assets under management | $ 346,800,000 | $ 294,900,000
Derivative |  |
Property, Plant and Equipment [Line Items] |  |
Cash or securities pledged as collateral | $ 0 |

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- Definition The fair value as of the balance sheet date of financial instruments and other positions owned by the entity and pledged to counterparties as collateral, including: (1) mortgages, mortgage-backed and asset backed securities; (2) US government and agency obligations; (3) state and municipal government obligations; (4) other sovereign government debt; (5) corporate obligations; (6) corporate equities; (7) principal investments; (8) derivative contracts; and (9) physical commodities. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 45 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=66007379&loc=d3e113888-111728 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 860 -SubTopic 30 -Section 50 -Paragraph 1A -Subparagraph (c)(2) -URI http://asc.fasb.org/extlink&oid=64858031&loc=SL6224234-111729 + Details
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- Definition Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues. + References No definition available. + Details
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