Organization (Details) ft² in Millions	Sep. 30, 2021 ft² property
Segment Reporting, Other Significant Reconciling Item [Line Items]
Number of major U.S. office markets	7
Number of real estate properties	54
Area of real estate property (in sq ft) | ft²	16.4
Percentage leased	86.00%
Redevelopment Asset
Segment Reporting, Other Significant Reconciling Item [Line Items]
Number of real estate properties	1