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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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