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Earnings Per OP Unit of MAALP Statement (details) - Limited Partner [Member] - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands | 3 Months Ended | 9 Months Ended
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Sep. 30, 2016 | Sep. 30, 2015 | Sep. 30, 2016 | Sep. 30, 2015
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Weighted average common units - basic |  | 79,449 | 79,374 | 79,432 | 79,356
Effect of dilutive securities | [1] | 0 | 0 | 246 | 0
Weighted average common shares - diluted |  | 79,449 | 79,374 | 79,678 | 79,356
Calculation of Basic Earnings Per Unit [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Income from continuing operations |  | $ 88,906 | $ 96,828 | $ 182,344 | $ 305,378
Income from continuing operations allocated to unvested restricted shares |  | (254) | (221) | (484) | (668)
Income from continuing operations available for common unitholders, adjusted |  | $ 88,652 | $ 96,607 | $ 181,860 | $ 304,710
Earnings per unit - basic |  | $ 1.12 | $ 1.22 | $ 2.29 | $ 3.84
Calculation of Diluted Earnings Per Unit [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Income from continuing operations |  | $ 88,906 | $ 96,828 | $ 182,344 | $ 305,378
Income from continuing operations allocated to unvested restricted shares | [1] | (254) | (221) | 0 | (668)
Income from continuing operations available for common unitholders, adjusted |  | $ 88,652 | $ 96,607 | $ 182,344 | $ 304,710
Earnings per unit - diluted |  | $ 1.12 | $ 1.22 | $ 2.29 | $ 3.84
Restricted Stock [Member] |  |  |  |  |
Earnings Per Share Disclosure [Line Items] |  |  |  |  |
Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount |  | 200 |  |  |
[1] | (1) For the three months ended September 30, 2016 and for both the three and nine months ended September 30, 2015, 0.2 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 -Glossary Antidilution -URI http://asc.fasb.org/extlink&oid=6505113 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Diluted Earnings Per Share -URI http://asc.fasb.org/extlink&oid=6510752 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Glossary Contingent Stock Agreement -URI http://asc.fasb.org/extlink&oid=6508534 Reference 4: 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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