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Partners' Capital of MAALP - Additional Information (Details) - USD ($) $ / shares in Units, $ in Millions | 9 Months Ended |
--- | --- | ---
Sep. 30, 2020 | Sep. 30, 2019 | Dec. 31, 2019
Schedule Of Capital Structure [Line Items] |  |  |
Operating partnership units outstanding | 118,428,070 | 118,140,136 |
General Partners' Capital Account, Units Outstanding | 114,369,812 | 114,065,859 |
Limited Partners' Capital Account, Units Outstanding | 4,058,258 | 4,074,277 |
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 | 4,058,258 | 4,074,277 |
Limited Partners' Capital Account | $ 470.6 | $ 529.7 |
Redeemable Capital Shares Par Or Stated Value Per Share | $ 115.95 | $ 130.01 |
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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