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Shareholders' Equity of MAA - Additional Information (Details) - USD ($) $ in Millions	6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Dec. 31, 2018
Equity [Line Items]
Common stock, shares outstanding	114,043,089	113,808,292	113,844,267
Total common shares and operating partnership units outstanding	118,133,172	117,943,960
Proceeds from Stock Options Exercised	$ 1.2	$ 0.6
Equity Option [Member]
Equity [Line Items]
Stock Issued During Period, Shares, New Issues	20,718	12,600
Noncontrolling Interest
Equity [Line Items]
Common Shares Issuable Upon Conversion Of Convertible Stock	4,090,083	4,135,668
Employee Stock Option [Member]
Equity [Line Items]
Common stock shares, outstanding option	60,442	95,838

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Amount of cash inflow from exercise of stock options granted under share-based compensation arrangement.

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