REGULATORY CAPITAL Regulatory Capital Requirements (narrative) (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	4.00%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Capital Conservation Buffer	2.50%
Value Of Trust Preferred Securities Included In Tier One Capital	$ 43.0
Acadia Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy	$ 2.5

Capital Conservation Buffer

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- Definition

Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets

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Value of trust preferred securities included in Tier I Capital.

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The minimum Total risk based capital ratio (total capital divided by risk weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 942

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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.

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The minimum amount of Tier 1 Leverage Capital for capital adequacy purposes divided by average assets as defined in the regulations.

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The minimum amount of Tier 1 Risk Based Capital required for capital adequacy purposes under the regulatory framework for prompt corrective action.

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The minimum Tier One Capital Ratio (Tier one capital divided by risk-weighted assets) required for capital adequacy purposes under the regulatory framework for prompt corrective action.

+ References

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

-Publisher FASB

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