Shareholders' Equity of MAA - Additional Information (Detail) (USD $)	3 Months Ended	9 Months Ended				3 Months Ended	9 Months Ended			9 Months Ended		3 Months Ended	9 Months Ended		12 Months Ended
	Sep. 30, 2014	Sep. 30, 2014	Sep. 30, 2013	Jun. 30, 2013	Feb. 25, 2013	Sep. 30, 2013 At The Market ATM Programs [Member]	Sep. 30, 2014 At The Market ATM Programs [Member]	Sep. 30, 2013 At The Market ATM Programs [Member]	Aug. 26, 2010 Maximum [Member]	Sep. 30, 2014 Noncontrolling Interest [Member]	Sep. 30, 2013 Noncontrolling Interest [Member]	Sep. 30, 2014 Parent Company [Member]	Sep. 30, 2014 Parent Company [Member]	Sep. 30, 2013 Parent Company [Member]	Dec. 31, 2013 Parent Company [Member]
Statement [Line Items]
Common stock, shares outstanding	75,242,266	75,242,266		42,744,978			4,134,989					75,242,266	75,242,266		74,830,726
Common Shares Issuable Upon Conversion Of Convertible Stock										4,202,123	1,701,955
Total common shares and operating partnership units outstanding	79,444,389	79,444,389	44,446,933
Common stock shares, outstanding option	81,654	81,654		0
Stock Issued During Period, Shares, Acquisitions		31,916,765								2,574,631
Agreement to sell common stock with financial service companies, shares					4,500,000				6,000,000
Stock Issued During Period, Shares, New Issues						0	0	365,011
Proceeds from issuance of common stock, net of applicable fees						$ 0		$ 24,800,000
Proceeds from Issuance of common stock						0		25,100,000					728,000	25,038,000
Share-based Compensation Arrangement by Share-based Payment Award, Options, Exercises in Period	40,338	263,259	0
Exercise of stock options												$ 2,400,000	$ 11,916,000	$ 0	$ 9,500,000
Treasury Stock, Shares, Acquired		9,292	4,805