Represents the period, for which commitments are generally made to make commercial draw notes.

No definition available.

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- Definition

Represents the period, for which commitments are generally made to make real estate and home equity loans.

+ References

No definition available.

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- Definition

For off-balance sheet financial instruments, the standard term for the agreement.

+ References

No definition available.

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- Definition

Refer to interest rate on fixed-rate commitments to make commercial draw notes.

+ References

No definition available.

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- Definition

Refer to interest rate on the fixed-rate commitments to make loans.

+ References

No definition available.

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- Definition

Refers to maturity period of the fixed-rate commitments to make loans.

+ References

No definition available.

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- Definition

The fair value of financial liabilities, which are not recognized in the financial statements (off-balance sheet) because they fail to meet some other criterion for recognition.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

The amount of expense provided in the period for legal costs incurred on or before the balance sheet date pertaining to resolved, pending or threatened litigation, including arbitration and mediation proceedings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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Amount awarded to other party in judgment or settlement of litigation.

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No definition available.

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- Definition

Amount of loss contingency liability.

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Amount of loss contingency liability expected to be resolved after one year or beyond the normal operating cycle, if longer.

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- Definition

The value (monetary amount) of the award the plaintiff seeks in the legal matter.

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COMMITMENTS AND CONTINGENCIES (Details) - USD ($) $ in Thousands			3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 15, 2018	Mar. 23, 2016	Jun. 30, 2018	Jun. 30, 2017	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Mar. 31, 2018	Jun. 30, 2016
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contingent obligations					$ 16,200
Legal accruals and settlements					$ 989	$ 850	$ 1,200
Pending Litigation
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contingent obligations				$ 2,300					$ 1,200
Damages sought		$ 4,000
Loss contingency, accrual, noncurrent				850
Legal accruals and settlements				$ 200
Chemung Canal Trust Company
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contingent obligations								$ 2,300
Legal accruals and settlements			$ 1,000
Litigation settlement amount	$ 3,300
Minimum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments period to make fixed-rate commercial draw notes					3 months
Minimum \| Fixed Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Interest rate on fixed-rate commitments to make loans					3.875%
Maturity period of fixed-rate commitments to make loans					5 years
Interest rate on fixed-rate commitments to make commercial draw notes (in hundredths)					3.50%
Maximum
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Commitments period to make real estate and home equity loans					60 days
Commitments period to make fixed-rate commercial draw notes					24 months
Off-balance sheet financial instruments, standard term					12 months
Maximum \| Fixed Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Interest rate on fixed-rate commitments to make loans					5.875%
Maturity period of fixed-rate commitments to make loans					30 years
Interest rate on fixed-rate commitments to make commercial draw notes (in hundredths)					6.25%
Commitments to make loans \| Fixed Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					$ 9,137	16,019
Commitments to make loans \| Variable Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					18,033	28,591
Unused lines of credit \| Fixed Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					848	1,604
Unused lines of credit \| Variable Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					212,601	200,353
Standby letters of credit \| Fixed Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					0	0
Standby letters of credit \| Variable Rate
Fair Value, Off-balance Sheet Risks, Disclosure Information [Line Items]
Contractual amounts of financial instruments with off-balance sheet risk					$ 16,161	$ 15,022