Earnings Per Common Share - Schedule of Earnings Per Share, Basic and Diluted (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Numerator:
Net income (loss) attributable to Acadia	$ 3,918	$ 19,410	$ 9,080	$ 10,996
Less: net income attributable to participating securities	(156)	(244)	(312)	(233)
Income (loss) from continuing operations net of income attributable to participating securities	$ 3,762	$ 19,166	$ 8,768	$ 10,763
Denominator:
Weighted average shares for basic earnings per share (in shares)	86,824,445	86,179,950	86,575,240	86,575,751
Effect of dilutive securities:
Employee unvested restricted shares (in shares)	0	0	0	0
Denominator for diluted earnings per share (in shares)	86,824,445	86,179,950	86,575,240	86,575,751
Basic and diluted earnings and basic loss per Common Share from continuing operations attributable to Acadia	$ 0.04	$ 0.22	$ 0.10	$ 0.12
Series A Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	188	188	188	188
Series A Preferred OP Units - Common Share Equivalent
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	25,067	25,067	25,067	25,067
Series C Preferred OP Units
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	126,593	126,593	126,593	126,593
Series C Preferred OP Units - Common Share Equivalent
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	439,556	439,556	439,556	439,556
Restricted shares
Anti-Dilutive Shares Excluded from Denominator:
Antidilutive securities excluded from computation of earnings per share (in shares)	70,827	76,433	70,827	76,433