Real Estate - Pro Forma Financial Information (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2017	Sep. 30, 2016
Acquisition and Disposition of Properties and Discontinued Operations [Abstract]
Acquisition related costs			$ 900	$ 5,500
Pro forma revenues	$ 63,253	$ 51,871	191,673	164,410
Pro forma income from continuing operations	368	1,092	26,439	19,504
Pro forma net income attributable to Acadia	$ 12,912	$ 6,839	$ 40,608	$ 54,201
Pro forma basic and diluted earnings per share (in dollars per share)	$ 0.15	$ 0.08	$ 0.48	$ 0.66

Acquisition and Disposition of Properties and Discontinued Operations [Abstract]

No definition available.

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- Definition

Business Acquisition, Pro Forma Earnings Per Share Basic and Diluted

+ References

No definition available.

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- Definition

Amount after tax of pro forma income from continuing operations as if the business combination had been completed at the beginning of a period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 805
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (h)(2)-(3)
-URI http://asc.fasb.org/extlink&oid=79982066&loc=d3e1392-128463

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- Definition

The pro forma net Income or Loss for the period as if the business combination or combinations had been completed at the beginning of a period.

+ References

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- Definition

The pro forma revenue for a period as if the business combination or combinations had been completed at the beginning of the period.

+ References

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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=84229725&loc=d3e1043-128460

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