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Equity method investment summarized financial information debt net.

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- Definition

Investment, Mandatory Redemption Term

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- Definition

Notes Receivable, Interest Rate

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- Definition

Number Of Investments

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- Definition

Sum of the carrying amounts as of the balance sheet date of all investments.

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- Definition

Amount, before allowance for credit loss, of financing receivable.

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- Definition

The number of real estate properties owned as of the balance sheet date.

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- Definition

The cash outflow from repayment of borrowings to finance the cost of construction.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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