Shareholders' Equity of MAA - Additional Information (Detail) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Dec. 31, 2018	Dec. 01, 2016
Preferred Stock, Liquidation Preference Per Share	$ 50.00
Preferred Stock, Redemption Date	Oct. 01, 2026
Preferred Stock, Redemption Price Per Share	$ 50.00
Common stock, shares outstanding	113,916,208	113,745,207
Total common shares and operating partnership units outstanding	118,021,379	117,886,987
Preferred Stock, Dividend Rate, Percentage	8.50%
Preferred Stock, Dividend Rate, Per-Dollar-Amount	$ 4.25
Preferred Stock, Liquidation Preference, Value	$ 43.4
Equity Option [Member]
Stock Issued During Period, Shares, New Issues	2,827	12,600
Noncontrolling Interest [Member]
Common Shares Issuable Upon Conversion Of Convertible Stock	4,105,171	4,141,780
Parent Company [Member]
Preferred Stock, Shares Outstanding	867,846		867,846
Preferred Stock, Liquidation Preference Per Share	$ 50		$ 50
Common stock, shares outstanding	113,916,208		113,844,267
Proceeds from Stock Options Exercised	$ 0.2	$ 0.6
Employee Stock Option [Member]
Common stock shares, outstanding option	87,788	95,838
Redeemable Preferred Stock [Member]
Preferred Stock, Shares Outstanding				867,846