Subsequent Events	6 Months Ended
Jun. 30, 2021
Subsequent Events [Abstract]
Subsequent Events	15. Subsequent Events Debt Extensions On July 7, 2021, Fund V extended the maturity of the $40.3 million loan on its Fairlane Green property to June 5, 2022 pursuant to an existing extension option. In connection with the extension, Fund V made a principal payment of $6.6 million. On July 21, 2021, Fund IV extended the maturity of the $22.9 million loan on its 146 Geary Street property to July 15, 2023 pursuant to an existing extension option. In connection with the extension, Fund IV made a principal payment of $3.6 million.

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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