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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 |

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- Definition Common Shares and Operating Partnership Units, Outstanding + References No definition available. + Details
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- Definition Common Shares Issuable upon Conversion of Convertible Stock + References No definition available. + Details
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- Definition Number of shares remaining for issuance. + References No definition available. + Details
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