Significant Accounting Policies - Concentrations of Credit Risk/Accounting Standards Updates (Details) - Annualized rent	3 Months Ended	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2022 tenant
Customer concentration
Concentration of Credit Risk
Number of tenants (tenants)		1
Maximum percentage of annualized rent for any one tenant not individually disclosed (percent) (more than)	5.00%	5.00%
Investment Property Concentration Risk | One Vanderbilt Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	14.30%
Investment Property Concentration Risk | 11 Madison Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	8.60%
Investment Property Concentration Risk | 1185 Avenue of the Americas
Concentration of Credit Risk
Percentage of concentration (percent)	6.90%
Investment Property Concentration Risk | 420 Lexington Ave
Concentration of Credit Risk
Percentage of concentration (percent)	6.80%
Investment Property Concentration Risk | 1515 Broadway
Concentration of Credit Risk
Percentage of concentration (percent)	6.40%
Investment Property Concentration Risk | 280 Park Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	5.60%
Investment Property Concentration Risk | 919 Third Avenue
Concentration of Credit Risk
Percentage of concentration (percent)	5.00%
Tenant 1 | Customer concentration
Concentration of Credit Risk
Percentage of concentration (percent)		6.00%