Number of full-service branches acquired.

No definition available.

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- Definition

Premium received upon sale of branch.

+ References

No definition available.

+ Details

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Namespace Prefix:	cac_
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Period Type:	instant

- Definition

Business Acquisition Purchase Price

+ References

No definition available.

+ Details

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- Definition

Premium on Deposits Sold

+ References

No definition available.

+ Details

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- Details

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- Definition

This element represents acquisition-related costs incurred to effect a business combination which costs have been expensed during the period. Such costs include finder's fees; advisory, legal, accounting, valuation, and other professional or consulting fees; general administrative costs, including the costs of maintaining an internal acquisitions department; and may include costs of registering and issuing debt and equity securities.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 805

-SubTopic 10

-Section 25

-Paragraph 23

-URI http://asc.fasb.org/extlink&oid=34752592&loc=d3e1043-128460

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- Definition

Amount classified as accounts, notes and loans receivable attributable to disposal group held for sale or disposed of.

+ References

+ Details

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Balance Type:	debit
Period Type:	instant

- Definition

Amount classified as other liabilities attributable to disposal group held for sale or disposed of.

+ References

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- Definition

Amount classified as property, plant and equipment attributable to disposal group held for sale or disposed of.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 45

-Paragraph 10

-URI http://asc.fasb.org/extlink&oid=6892542&loc=d3e1107-107759

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 2

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1436-107760

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (a)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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- Definition

The gain (loss) resulting from the sale of a disposal group that is not a discontinued operation. It is included in income from continuing operations before income taxes in the income statement.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 205

-SubTopic 20

-Section 50

-Paragraph 1

-Subparagraph (b)

-URI http://asc.fasb.org/extlink&oid=6360339&loc=d3e1361-107760

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 360

-SubTopic 10

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=8077374&loc=d3e2443-110228

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- Details

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Branch Acquisition and Divestiture (Details) (USD $)	12 Months Ended			0 Months Ended
Branch Acquisition and Divestiture (Details) (USD $)	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Oct. 04, 2013	Oct. 26, 2012 branch
Business Acquisition [Line Items]
Gain on branch divestiture	$ 0	$ 2,742,000	$ 0
Branch acquisition and divestiture costs	0	374,000	2,324,000
Branch Acquisition [Member]
Business Acquisition [Line Items]
Number of full-service branches acquired					15
Payments to Acquire Businesses, Gross					12,000,000
Premium received upon sale of branch					3,300,000
Branches To Be Disposed Of [Member]
Business Acquisition [Line Items]
Deposits and Borrowings Divested				85,900,000
Loans Divested				46,000,000
Real Estate and Equipment Divested				602,000
Premium on Deposits Sold				3.50%
Gain on branch divestiture				$ 2,700,000