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Earnings Per OP Unit of MAALP (Details) - Limited Partner [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Earnings Per Unit Disclosure |  |  |  |
Weighted average common units - basic |  | 117,617 | 82,661 | 79,361
Weighted Average Number Diluted Shares Outstanding Adjustment |  | 280 | 298 | 0
Weighted average common shares - diluted |  | 117,897 | 82,959 | 79,361
Earnings Per Share, Basic [Abstract] |  |  |  |
Dividends, Preferred Stock, Cash |  | $ 3,688 | $ 924 | $ 0
Earnings per unit - basic |  | $ 2.86 | $ 2.70 | $ 4.41
Diluted Earnings Per Unit |  | $ 2.86 | $ 2.70 | $ 4.41
Calculation of Basic Earnings Per Unit [Member] |  |  |  |
Earnings Per Share, Basic [Abstract] |  |  |  |
Income from Continuing Operations, Including Portion Attributable to Noncontrolling Interest |  | $ 340,536 | $ 224,402 | $ 350,745
Income from continuing operations allocated to unvested restricted shares |  | 535 | 574 | 772
Dividends, Preferred Stock, Cash |  | (3,688) | (307) | 0
Income from continuing operations available for common unitholders, adjusted |  | $ 336,313 | $ 223,521 | $ 349,973
Earnings per unit - basic |  | $ 2.86 | $ 2.70 | $ 4.41
Calculation of Diluted Earnings Per Unit [Member] |  |  |  |
Earnings Per Share, Basic [Abstract] |  |  |  |
Income from Continuing Operations, Including Portion Attributable to Noncontrolling Interest |  | $ 340,536 | $ 224,402 | $ 350,745
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 unitholders, adjusted |  | $ 336,848 | $ 224,095 | $ 349,973
Diluted Earnings Per Unit |  | $ 2.86 | $ 2.70 | $ 4.41
Restricted Stock [Member] |  |  |  |
Earnings Per Share, Basic [Abstract] |  |  |  |
Effect of dilutive securities (units) | [1] |  |  | 100
[1] | 0.1 million potentially dilutive securities and their related income are not included in the diluted earnings per unit calculations as they are not dilutive.

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