XML 19 R70.htm IDEA: XBRL DOCUMENT v2.4.1.9

RELATED PARTY TRANSACTIONS (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Loans to Related Parties [Roll Forward]
Balance at beginning of year	$ 26,408,000us-gaap_NotesReceivableRelatedParties	$ 25,390,000us-gaap_NotesReceivableRelatedParties
New loans or additional advances	33,282,000us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions	30,056,000us-gaap_LoansAndLeasesReceivableRelatedPartiesAdditions
Repayments	(21,888,000)us-gaap_LoansAndLeasesReceivableRelatedPartiesCollections	(29,038,000)us-gaap_LoansAndLeasesReceivableRelatedPartiesCollections
Balance at end of year	37,802,000us-gaap_NotesReceivableRelatedParties	26,408,000us-gaap_NotesReceivableRelatedParties
Deposit Liabilities	$ 12,000,000us-gaap_RelatedPartyDepositLiabilities	$ 9,800,000us-gaap_RelatedPartyDepositLiabilities
Minimum [Member]
Related Party Transactions [Line Items]
Related party principal ownership threshold (in hundredths)	10.00%chmg_RelatedPartyPrincipalOwnershipThreshold / us-gaap_RangeAxis = us-gaap_MinimumMember

X

- Definition

For a designation as a related party, the threshold percentage of principal ownership in an entity, above which the party is considered a related party..

+ References

No definition available.

+ Details

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Namespace Prefix:	chmg_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	duration

X

- Definition

Reflects the amount of new advances made to related parties in the form of loan and lease receivables.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.9-03.7(e))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

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X

- Definition

Reflects the amount of collections received from related parties to reduce the carrying amounts of loans and leases receivable due from them.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=6457730&loc=d3e39549-107864



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-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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-Section S99

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-Subparagraph (SX 210.9-03.7(e))

-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878



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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph e

-Article 9

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X

- Definition

For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(k)(1))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690



Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 850

-SubTopic 10

-Section 50

-Paragraph 1

-Subparagraph (d)

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Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

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-Number 210

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Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

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Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.3)

-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910



Reference 6: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Glossary Related Parties

-URI http://asc.fasb.org/extlink&oid=16382449

+ Details

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X

- Definition

Amount of deposits held by the entity for a related party (entity, shareholder, employee).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 235

-SubTopic 10

-Section S99

-Paragraph 1

-Subparagraph (SX 210.4-08.(k))

-URI http://asc.fasb.org/extlink&oid=26873400&loc=d3e23780-122690

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- Details

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