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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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- 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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