Subsequent Events (Details) - Subsequent Event - property	Jan. 12, 2022	Jan. 13, 2022
SoHo Properties
Subsequent Event [Line Items]
Number of properties sold		2
Operational | Long-Term Performance Award 2022
Subsequent Event [Line Items]
Percentage breakdown of awards	50.00%
Operational | Long-Term Performance Award 2022 | Comparable FFO per Share
Subsequent Event [Line Items]
Percentage breakdown of awards	75.00%
Operational | Long-Term Performance Award 2022 | ESG Performance Metrics
Subsequent Event [Line Items]
Percentage breakdown of awards	25.00%
Relative | Long-Term Performance Award 2022
Subsequent Event [Line Items]
Percentage breakdown of awards	50.00%
Percentage reduction threshold	30.00%
Relative | Long-Term Performance Award 2022 | SNL US Office REIT Index
Subsequent Event [Line Items]
Percentage of benchmark	50.00%
Relative | Long-Term Performance Award 2022 | Northeast Peer Group Custom Index
Subsequent Event [Line Items]
Percentage of benchmark	50.00%
Absolute | Long-Term Performance Award 2022
Subsequent Event [Line Items]
Percentage reduction threshold	30.00%
Absolute | Maximum | Long-Term Performance Award 2022
Subsequent Event [Line Items]
Percent vested, year four	50.00%
Percent vested, year five	50.00%