Commitments and Contingencies - Major Customers and Other Concentrations (Details) - Customer concentration risk - Rental revenue - office_property	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Concentration Risk [Line Items]
Number of properties	3	3	3
Empire State Building
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	29.60%	29.90%	31.70%
One Grand Central Place
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	12.80%	12.40%	12.60%
111 West 33rd Street
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	10.80%	11.20%	11.30%
Tenant 1
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	6.80%	6.40%	4.60%
Tenant 2
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	2.50%	2.00%	3.30%
Tenant 3
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	2.10%		2.80%
Tenant 4
Concentration Risk [Line Items]
Concentration risk percentage (as a percent)	2.10%		2.10%