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Debt and Preferred Equity Investments (Details) $ in Millions | 3 Months Ended | 12 Months Ended |
--- | --- | --- | ---
Mar. 31, 2021 investment property | Dec. 31, 2018 USD ($) | Dec. 31, 2020 USD ($) property
Summary of Investment Holdings [Line Items] |  |  |
Number of properties | property | 81 |  |
Austin Preferred Equity Investment |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Investments |  |  | $ 50.0
Number of properties | property |  |  | 2
Annual preferred return on invested capital | 9.00% |  |
Mandatory redemption term | 1 year |  |
Brandywine 1919 Ventures |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Debt, net |  | $ 44.4 |
Note receivable |  | $ 44.4 |
Notes receivable, interest rate |  | 4.00% |
Repayment of construction loan |  | $ 88.8 |
Notes Receivable |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Number of investments | investment | 1 |  |
Preferred Equity Investment |  |  |
Summary of Investment Holdings [Line Items] |  |  |
Number of investments | investment | 1 |  |

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