Financing Receivable in Process of Foreclosure

No definition available.

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- Definition

Financing Receivables Impaired Troubled Debt Restructuring Non-Performing

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Financing Receivables, Impaired, Troubled Debt Restructuring, Performing

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Foregone interest.

+ References

No definition available.

+ Details

Name:	cac_LoansAndLeasesReceivableImpairedInterestIncomeForegone
Namespace Prefix:	cac_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

loans in foreclosure percentage of non-performing loans

+ References

No definition available.

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of months to resolve foreclosure

+ References

No definition available.

+ Details

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Data Type:	xbrli:integerItemType
Balance Type:	na
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

- Definition

number of days pas due

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
Balance Type:	na
Period Type:	instant

- Definition

term to maturity

+ References

No definition available.

+ Details

Name:	cac_Termtomaturity
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Data Type:	us-types:durationStringItemType
Balance Type:	na
Period Type:	duration

- 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.

+ Details

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Balance Type:	na
Period Type:	duration

- Definition

For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 18
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6351-108592

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13531-108611

Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 275
-SubTopic 10
-Section 50
-Paragraph 20
-URI http://asc.fasb.org/extlink&oid=51801978&loc=d3e6404-108592

Reference 4: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 825
-SubTopic 10
-Section 50
-Paragraph 21
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=49121117&loc=d3e13537-108611

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Balance Type:	na
Period Type:	duration

- Definition

A valuation allowance for financing receivables that are expected to be uncollectible.

+ 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 (c)(1)
-URI http://asc.fasb.org/extlink&oid=49124121&loc=SL6953423-111524

+ Details

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

- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=cac_HPFCPortfolioSegmentMember
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- Details

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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_ResidentialPortfolioSegmentMember
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- Details

Name:	us-gaap_FinancingReceivableRecordedInvestmentByClassOfFinancingReceivableAxis=us-gaap_LoansReceivableMember
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- Details

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- Details

Name:	us-gaap_ConcentrationRiskByTypeAxis=cac_LoanConcentrationRiskMember
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- Details

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- Details

Name:	us-gaap_ConcentrationRiskByBenchmarkAxis=us-gaap_CommercialRealEstatePortfolioSegmentMember
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Data Type:	na
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- Details

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Loans and Allowance for Loan Losses (Additional Information) (Details) $ in Thousands	12 Months Ended
	Dec. 31, 2015 USD ($)	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)	Dec. 31, 2012 USD ($)
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit losses	$ 21,166	$ 21,116	$ 21,590	$ 23,044
Foregone interest	$ 586	842	990
Number of Portfolio Concentration Industries	0
HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit losses	$ 24	0	0
Unallocated Financing Receivables [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit losses	$ 0	2,384	2,671	2,862
Residential real estate loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term to maturity (years)	30 years
Financing receivable, allowance for credit losses	$ 4,545	4,899	5,603	6,996
Financing Receivable in Process of Foreclosure	2,900	4,900
Loans Receivable [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans restructured due to credit difficulties that are now performing	4,800	4,500
Financing Receivables Impaired Troubled Debt Restructuring Non-Performing	446	1,400
Consumer loans
Accounts, Notes, Loans and Financing Receivable [Line Items]
Financing receivable, allowance for credit losses	$ 193	$ 281	$ 319	$ 184
loans in foreclosure percentage of non-performing loans	32.00%	61.00%
Minimum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Months	18
Minimum [Member] \| HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term to maturity (years)	7 years
Maximum [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of Months	24
Maximum [Member] \| HPFC Portfolio Segment [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Term to maturity (years)	10 years
Total Loan Portfolio [Member] \| Loan Concentration Risk [Member] \| Non-Residential Building Operators Industry Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	10.00%
Commercial Real Estate Portfolio Segment [Member] \| Loan Concentration Risk [Member] \| Non-Residential Building Operators Industry Sector [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Concentration Risk, Percentage	27.00%
HPFC Subsidiary [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Number of days past due	45