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Partners' Capital of MAALP - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Schedule Of Capital Structure [Line Items] |  |
Operating partnership units outstanding | 118,431,384 | 118,313,567
General Partners' Capital Account, Units Outstanding | 114,373,727 | 114,246,393
Limited Partners' Capital Account, Units Outstanding | 4,057,657 | 4,067,174
Preferred Stock, Shares Outstanding | 867,846 | 867,846
Redeemable Preferred Stock [Member] |  |
Schedule Of Capital Structure [Line Items] |  |
Preferred Stock, Shares Outstanding | 867,846 |
Noncontrolling Interest |  |
Schedule Of Capital Structure [Line Items] |  |
Common Shares Issuable Upon Conversion Of Convertible Stock | 4,057,657 | 4,067,174
Limited Partners' Capital Account | $ 514.1 | $ 536.3
Redeemable Capital Shares Par Or Stated Value Per Share | $ 126.69 | $ 131.86
M A A L P |  |
Schedule Of Capital Structure [Line Items] |  |
Limited Liability Company (LLC) or Limited Partnership (LP), Managing Member or General Partner, Ownership Interest | 96.60% | 96.60%

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- Definition Percentage investment held by the managing member or general partner of the limited liability company (LLC) or limited partnership (LP). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 272 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=6373374&loc=d3e70478-108055 + Details
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