Allowance for Credit Losses, Related to Troubled Debt Restructured Loans

No definition available.

Name:	cac_AllowanceForCreditLossesRelatedToTroubledDebtRestructuredLoans
Namespace Prefix:	cac_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

allowance methodology number of changes during the period

+ References

No definition available.

+ Details

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Namespace Prefix:	cac_
Data Type:	xbrli:integerItemType
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Period Type:	duration

- Definition

Lodging loans expressed as a percentage of the total commercial real estate loans.

+ References

No definition available.

+ Details

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Namespace Prefix:	cac_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Non-residential building operator loans expressed as a percentage of the total commercial real estate loans.

+ References

No definition available.

+ Details

Name:	cac_CreditConcentrationRiskOfNonresidentialBuildingOperatorLoansExpressedAsPercentageOfTotalCommercialRealEstateLoans
Namespace Prefix:	cac_
Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Financing Receivable in Process of Foreclosure

+ References

No definition available.

+ Details

Name:	cac_FinancingReceivableinProcessofForeclosure
Namespace Prefix:	cac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing Receivables Impaired Troubled Debt Restructuring Non-Performing

+ References

No definition available.

+ Details

Name:	cac_FinancingReceivablesImpairedTroubledDebtRestructuringNonPerforming
Namespace Prefix:	cac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing Receivables, Impaired, Troubled Debt Restructuring, Performing

+ References

No definition available.

+ Details

Name:	cac_FinancingReceivablesImpairedTroubledDebtRestructuringPerforming
Namespace Prefix:	cac_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Number of Portfolio Concentration Industries

+ References

No definition available.

+ Details

Name:	cac_NumberofPortfolioConcentrationIndustries
Namespace Prefix:	cac_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	duration

- Details

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Data Type:	xbrli:stringItemType
Balance Type:	na
Period Type:	duration

- Definition

The effect of a change in method or methods for calculating the allowance for credit losses on the current period provision.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 11B

-Subparagraph (d)

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953423-111524

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Number of financing receivables that have been modified by troubled debt restructurings within the previous 12 months and for which there was a payment default.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 34

-URI http://asc.fasb.org/extlink&oid=35738203&loc=SL6953682-111524

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Period Type:	duration

- Definition

The gains (losses) included in earnings that represent the difference between the sale price and the carrying value of loans made to finance real estate acquisitions. This element refers to the gain (loss) and not to the cash proceeds of the sale. This element is a noncash adjustment to net income when calculating net cash generated by operating activities using the indirect method.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 230

-SubTopic 10

-Section 45

-Paragraph 28

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=31042434&loc=d3e3602-108585

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Reflects the amount of additional interest income that would have been recorded if impaired or nonperforming loans were instead current, in compliance with their original terms, and outstanding throughout the reporting period or since origination (if held for part of the period).

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 40

-Section 50

-Paragraph 1

-URI http://asc.fasb.org/extlink&oid=25495931&loc=d3e18794-111554

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The carrying amount of mortgage loans on real estate that were sold during the reporting period.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 10

-Section S99

-Paragraph 6

-Subparagraph (SX 210.5-04.(c) Schedule IV)

-URI http://asc.fasb.org/extlink&oid=27047687&loc=d3e5864-122674

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 29

-Article 12

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule IV

-Article 5

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 948

-SubTopic 310

-Section S99

-Paragraph 1

-Subparagraph (SX 210.12-29.6)

-URI http://asc.fasb.org/extlink&oid=6589523&loc=d3e617274-123014

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

The number of real estate properties owned as of the balance sheet date.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant

- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 45

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28367877&loc=d3e4437-111522

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 28

-Article 12

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Paragraph c

-Subparagraph Schedule III

-Article 5

+ Details

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Namespace Prefix:	us-gaap_
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Balance Type:	debit
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LOANS AND ALLOWANCE FOR LOAN LOSSES (Narrative) (Details) (USD $)	3 Months Ended			9 Months Ended		12 Months Ended
	Sep. 30, 2014 loan	Jun. 30, 2014 revision	Sep. 30, 2013	Sep. 30, 2014 loan industry	Sep. 30, 2013	Dec. 31, 2013 industry
Accounts, Notes, Loans and Financing Receivable [Line Items]
Gain (loss) on sale of mortgage loans				$ 17,000	$ 684,000
Allowance methodology number of changes during the period		1
Financing receivable, allowance for credit losses, effect of change in method		165,000
Number of Portfolio Concentration Industries				2		2
Non-residential building operator loans expressed as a percentage of the total commercial real estate loans	26.00%			26.00%		28.00%
Lodging loans expressed as a percentage of the total commercial real estate loans	26.00%			26.00%		25.00%
Loans and Leases Receivable, Impaired, Interest Lost on Nonaccrual Loans	192,000		256,000	647,000	738,000
Allowance for credit Losses related to troubled debt restructuring	691,000			691,000		656,000
Financing Receivable, Modifications, Subsequent Default, Number of Contracts	0			0
Other real estate owned	1,566,000			1,566,000		2,195,000
Fixed Rate Residential Mortgage
Accounts, Notes, Loans and Financing Receivable [Line Items]
Mortgage Loans sold on secondary market			7,300,000	399,000	28,200,000
Gain (loss) on sale of mortgage loans			32,000	17,000	684,000
Loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Allowance for credit Losses related to troubled debt restructuring	691,000			691,000		656,000
Loans restructured due to credit difficulties that are now performing	5,200,000			5,200,000		5,500,000
Financing Receivables Impaired Troubled Debt Restructuring Non-Performing	1,500,000			1,500,000		1,600,000
Residential real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing Receivable in Process of Foreclosure	6,000,000			6,000,000		4,400,000
Commercial Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Real Estate Properties	6			6		6
Other real estate owned	1,000,000			1,000,000		1,200,000
Residential Real Estate
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Real Estate Properties	11			11		10
Other real estate owned	$ 554,000			$ 554,000		$ 1,000,000