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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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- Definition Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 260 -SubTopic 10 -Section 50 -Paragraph 1 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=6371337&loc=d3e3550-109257 + Details
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