REGULATORY CAPITAL Regulatory Capital Requirements (narrative) (Details) - USD ($) $ in Thousands	Oct. 08, 2015	Jun. 30, 2016	Dec. 31, 2015
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Required for Capital Adequacy to Risk Weighted Assets		8.625%	8.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.625%	6.00%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		5.125%	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		$ 43,000	$ 43,000
Subordinated Debt	$ 15,000	58,677	$ 58,599
Debt Instrument, Term	10 years
Debt Instrument, Interest Rate, Stated Percentage	5.50%
Acadia Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Tier One Risk Based Capital Required for Capital Adequacy		$ 2,500
Acadia Trust [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Required for Capital Adequacy to Risk Weighted Assets		8.625%	8.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.625%	6.00%
Common Equity Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		5.125%	4.50%
Tier One Leverage Capital Required for Capital Adequacy to Average Assets		4.00%	4.00%
Minimum [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Capital Required for Capital Adequacy to Risk Weighted Assets		8.00%
Tier One Risk Based Capital Required for Capital Adequacy to Risk Weighted Assets		6.00%
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%
Capital Conservation Buffer		0.625%
Tier II Capital [Domain]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Subordinated Debt		$ 15,000
Subordinated Debt [Member]
Compliance with Regulatory Capital Requirements under Banking Regulations [Line Items]
Subordinated Debt			$ 15,000

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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
-SubTopic 505
-Section 50
-Paragraph 1
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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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Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Stated interest rate of the subordinated debt.

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Including the current and noncurrent portions, carrying value as of the balance sheet date of subordinated debt (with initial maturities beyond one year or beyond the operating cycle if longer). Subordinated debt places a lender in a lien position behind debt having a higher priority of repayment in liquidation of the entity's assets.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03.16)
-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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Reference 3: http://www.xbrl.org/2003/role/presentationRef
-Publisher SEC
-Name Regulation S-X (SX)
-Number 210
-Section 02
-Article 5
-Subsection 19, 20, 22

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-Name Staff Accounting Bulletin (SAB)
-Number Topic 10
-Section F

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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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-Name Accounting Standards Codification
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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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