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Earnings Per Common Share of MAA Earnings Per Common Share of MAA (Details) - Parent Company [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2017 | Sep. 30, 2016 | Sep. 30, 2017 | Sep. 30, 2016
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Weighted average common shares - basic |  | 113,434 | 75,302 | 113,392 | 75,276
Weighted average partnership units outstanding | [1] | 0 | 0 | 0 | 4,156
Effect of dilutive securities | [2] | 219 | 0 | 270 | 246
Weighted average common shares - diluted |  | 113,653 | 75,302 | 113,662 | 79,678
Dividends, Preferred Stock, Cash |  |  |  | $ 2,766 | $ 0
Calculation of Basic Earnings per Share [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Income from continuing operations |  | $ 118,958 | $ 88,906 | 212,529 | 182,344
Income from continuing operations attributable to noncontrolling interests |  | (4,249) | (4,627) | (7,600) | (9,508)
Income from continuing operations allocated to unvested restricted shares |  | (181) | (254) | (337) | (485)
Dividends, Preferred Stock, Cash |  | (922) | 0 | (2,766) | 0
Income from continuing operations available for common shareholders, adjusted |  | $ 113,606 | $ 84,025 | $ 201,826 | $ 172,351
Earnings per share - basic |  | $ 1.00 | $ 1.12 | $ 1.78 | $ 2.29
Calculation of Diluted Earnings per Share [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Income from continuing operations |  | $ 118,958 | $ 88,906 | $ 212,529 | $ 182,344
Income from continuing operations attributable to noncontrolling interests | [1] | (4,249) | (4,628) | (7,600) | 0
Income from continuing operations allocated to unvested restricted shares | [2] | 0 | (254) | 0 | 0
Dividends, Preferred Stock, Cash |  | (922) |  | (2,766) | 0
Income from continuing operations available for common shareholders, adjusted |  | $ 113,787 | $ 84,024 | $ 202,163 | $ 182,344
Earnings per share - diluted |  | $ 1.00 | $ 1.12 | $ 1.78 | $ 2.29
Limited Partnership Units [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  |  | 4,200 |
Restricted Stock [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  |  | 200 |  |
[1] | (1) For both the three and nine months ended September 30, 2017 and the three months ended September 30, 2016, 4.2 million OP Units and their related income are not included in the diluted earnings per share calculations as they are not dilutive.
[2] | (2) For the three months ended September 30, 2016, 0.2 million potentially dilutive securities and their related income are not included in the diluted earnings per share calculations as they are not dilutive.

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