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Earnings Per Common Share of MAA (Details) - Parent Company [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 12 Months Ended
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Dec. 31, 2017 | Sep. 30, 2017 | Jun. 30, 2017 | Mar. 31, 2017 | Dec. 31, 2016 | Sep. 30, 2016 | Jun. 30, 2016 | Mar. 31, 2016 | Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Earnings Per Share Disclosure |  |  |  |  |  |  |  |  |  |  |  |
Weighted average common shares, basic |  |  |  |  |  |  |  |  |  | 113,407 | 78,502 | 75,176
Weighted Average Number Diluted Shares Outstanding Adjustment |  |  |  |  |  |  |  |  |  | 280 | 298 | 0
Weighted average common shares - diluted |  |  |  |  |  |  |  |  |  | 113,687 | 78,800 | 75,176
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest |  | $ 128,007 | $ 118,958 | $ 50,155 | $ 43,416 | $ 42,058 | $ 88,906 | $ 47,630 | $ 45,808 | $ 340,536 | $ 224,402 | $ 350,745
Dividends, Preferred Stock, Cash |  |  |  |  |  |  |  |  |  | 3,688 | 924 | 0
Calculation of Basic Earnings per Share [Member] |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share Disclosure |  |  |  |  |  |  |  |  |  |  |  |
Net Income (Loss), Including Portion Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  | 340,536 | 224,402 | 350,745
Income from Continuing Operations Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  | (12,157) | (12,180) | (18,458)
Income from continuing operations allocated to unvested restricted shares |  |  |  |  |  |  |  |  |  | (535) | (572) | (772)
Dividends, Preferred Stock, Cash |  |  |  |  |  |  |  |  |  | (3,688) | (307) | 0
Income from continuing operations available for common shareholders, adjusted |  |  |  |  |  |  |  |  |  | $ 324,156 | $ 211,343 | $ 331,515
Basic Earnings Per Share |  |  |  |  |  |  |  |  |  | $ 2.86 | $ 2.69 | $ 4.41
Calculation of Diluted Earnings per Share [Member] |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share Disclosure |  |  |  |  |  |  |  |  |  |  |  |
Income from Continuing Operations, Including Portion Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  | $ 340,536 | $ 224,402 | $ 350,745
Income from Continuing Operations Attributable to Noncontrolling Interest |  |  |  |  |  |  |  |  |  | (12,157) | (12,180) | (18,458)
Income from continuing operations allocated to unvested restricted shares |  |  |  |  |  |  |  |  |  | 0 | 0 | (772)
Dividends, Preferred Stock, Cash |  |  |  |  |  |  |  |  |  | (3,688) | (307) | 0
Income from continuing operations available for common shareholders, adjusted |  |  |  |  |  |  |  |  |  | $ 324,691 | $ 211,915 | $ 331,515
Diluted Earnings Per Share |  |  |  |  |  |  |  |  |  | $ 2.86 | $ 2.69 | $ 4.41
Limited Partnership Units [Member] |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share Disclosure |  |  |  |  |  |  |  |  |  |  |  |
Effect of dilutive securities (shares) | [1] |  |  |  |  |  |  |  |  | 4,200 |  |
Restricted Stock [Member] |  |  |  |  |  |  |  |  |  |  |  |
Earnings Per Share Disclosure |  |  |  |  |  |  |  |  |  |  |  |
Effect of dilutive securities (shares) |  |  |  |  |  |  |  |  |  |  |  | 100
[1] | 4.2 million OP units and their related income are not included in the diluted earnings per share calculations as they are not dilutive.

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