Subsequent Events	3 Months Ended
Mar. 31, 2021
Subsequent Events [Abstract]
Subsequent Events	15. Subsequent Events Dispositions On April 2, 2021, Fund IV entered into an agreement to sell its Airport Mall, Shaw’s North Windham, Shaw’s Waterville and Wells Plaza properties for a total of $40.4 million. Debt Extensions On April 6, 2021 Fund IV extended the maturity of the $23.1 million mortgage on its Lincoln Place property to March 13, 2022. On April 27, 2021, Fund IV extended the maturity of the $18.5 million mortgage on an unconsolidated property, 650 Bald Hill Road, to June 27, 2021. Fund V Extension As of April 8, 2021, Fund V’s investment period was extended by one year to August 25, 2022. Note Receivable On April 20, 2021, the Company issued a note for $16.0 million to the partner of its MCB venture, collateralized by real estate.

The entire disclosure for significant events or transactions that occurred after the balance sheet date through the date the financial statements were issued or the date the financial statements were available to be issued. Examples include: the sale of a capital stock issue, purchase of a business, settlement of litigation, catastrophic loss, significant foreign exchange rate changes, loans to insiders or affiliates, and transactions not in the ordinary course of business.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-URI http://asc.fasb.org/topic&trid=2122774

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 855
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=6842918&loc=SL6314017-165662

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