REGULATORY CAPITAL (Details) - USD ($) $ in Millions	Sep. 30, 2015	Dec. 31, 2014
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital to Risk Weighted Assets	14.76%	15.16%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Tier One Risk Based Capital to Risk Weighted Assets	13.67%	13.97%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	4.00%
Common Equity Tier I Risk Based Capital Ratio	11.44%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%
Excess Tier One Leverage Capital to Average Assets	9.41%	9.26%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Acadia Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy	$ 2.5
Subsidiaries [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital to Risk Weighted Assets	13.47%	13.85%
Capital Required for Capital Adequacy to Risk Weighted Assets	8.00%	8.00%
Capital Required to be Well Capitalized to Risk Weighted Assets	10.00%	10.00%
Tier One Risk Based Capital to Risk Weighted Assets	12.37%	12.65%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	6.00%	4.00%
Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	8.00%	6.00%
Common Equity Tier I Risk Based Capital Ratio	12.37%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets	4.50%
Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets	6.50%
Excess Tier One Leverage Capital to Average Assets	8.52%	8.38%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets	4.00%	4.00%
Tier One Leverage Capital Required to be Well Capitalized to Average Assets	5.00%	5.00%

Common Equity Tier I To Total Risk Weighted Assets Capital Ratio

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

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Common Equity Tier One Risk Based Capital Required to be Well Capitalized to Risk Weighted Assets

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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.

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The Total risk based capital ratio (total capital divided by risk weighted assets) required to be categorized as "well capitalized", in the regulatory framework for prompt corrective action.

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Total Capital divided by risk weighted assets as defined in the regulations.

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The amount of excess Tier 1 Leverage Capital divided by average assets as defined in the regulations.

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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.

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The Tier 1 capital ratio (Tier 1 capital divided by risk weighted assets) required to be categorized as "well capitalized" under the regulatory framework for prompt corrective action.

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Tier 1 capital divided by risk weighted assets as defined by regulations.

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