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Shareholders' Equity of MAA - Additional Information (Details) - USD ($)
 12 Months Ended
Dec. 31, 2020
Dec. 31, 2019
Dec. 31, 2018
Equity [Line Items]      
Common stock, shares outstanding 114,373,727 114,246,393  
Total common shares and operating partnership units outstanding 118,431,384 118,313,567  
Common stock, shares authorized 145,000,000 145,000,000  
At The Market Offering      
Equity [Line Items]      
Common stock shares sold 146,301    
Net proceeds from share issued $ 19,600,000    
Remaining common stock to sale 3,900,000    
Maximum [Member] | At The Market Offering      
Equity [Line Items]      
Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized 4,000,000.0    
Dividend And Distribution Reinvestment And Share Purchase Plan      
Equity [Line Items]      
Common stock issued for shareholders to reinvest distributions (shares) 8,259 16,219 9,721
Dividend And Distribution Reinvestment And Share Purchase Plan | Minimum [Member]      
Equity [Line Items]      
Optional cash investments in common shares $ 250    
Dividend And Distribution Reinvestment And Share Purchase Plan | Maximum [Member]      
Equity [Line Items]      
Optional cash investments in common shares $ 5,000    
Common stock, shares authorized 1,940,500    
Discount rate on sale of common stock (percent) 5.00%    
Noncontrolling Interest      
Equity [Line Items]      
Common Shares Issuable Upon Conversion Of Convertible Stock 4,057,657 4,067,174