LOANS AND ALLOWANCE FOR LOAN LOSSES (Troubled Debt Restructuring Loans) (Details) $ in Thousands	Mar. 31, 2020 USD ($) loan	Dec. 31, 2019 USD ($) loan
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	26	27
Recorded Investment	$ 3,447	$ 3,629
Specific Reserve	$ 447	$ 463
Residential Real Estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	21	22
Recorded Investment	$ 2,692	$ 2,869
Specific Reserve	$ 324	$ 364
Commercial Real Estate
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	2	2
Recorded Investment	$ 338	$ 338
Specific Reserve	$ 34	$ 30
Commercial
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	2	2
Recorded Investment	$ 118	$ 123
Specific Reserve	$ 0	$ 0
Consumer
Financing Receivable, Modifications [Line Items]
Number of Contracts \| loan	1	1
Recorded Investment	$ 299	$ 299
Specific Reserve	$ 89	$ 69

Allowance for Credit Losses, Related to Troubled Debt Restructured Loans

No definition available.

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Balance Type:	credit
Period Type:	instant

- Definition

Financing Receivable Modifications Number Of Contracts Outstanding

+ References

No definition available.

+ Details

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Namespace Prefix:	cac_
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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.

+ Details

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- Definition

The amount of the outstanding recorded investment related to financing receivables that have been modified by troubled debt restructurings.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=82895541&loc=d3e18845-111554

+ Details

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- Details

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