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Investment in Unconsolidated Joint Venture - Additional Information (Detail) $ in Millions				12 Months Ended
	Dec. 31, 2024	Oct. 18, 2017 USD ($)	Jun. 01, 2017 USD ($)	Dec. 31, 2024 Tenants	Dec. 31, 2023 Tenants	Sep. 13, 2024 USD ($)	Oct. 30, 2013 USD ($)
Schedule of Equity Method Investments [Line Items]
Number Of Tenants \| Tenants				2	2
Cravath Swaine Moore LLP [Member]
Schedule of Equity Method Investments [Line Items]
Lease expiration date				Aug. 31, 2024
Worldwide Plaza [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage	50.10%			50.10%			48.90%
Aggregate cost			$ 276.7				$ 220.1
Agreed upon value							1,300.0
Notes payable							$ 875.0
Additional acquire percentage			49.90%
Purchase obligation			$ 1,400.0
Mortgage notes payable			$ 875.0
Joint venture partner's right to maintain minimum ownership percentage			1.20%
Debt refinance amount		$ 1,200.0
Cash received from sale and excess proceeds from financing		446.5
Defeasance and prepayment costs		108.3
Reserved amount		$ 90.7
Debt blended rate		3.98%
Maturity date				2027-11
Interest payment						$ 0.8
Property selling percentage				100.00%
Option to purchase percentage of property				100.00%
Property purchase option period				45 days
Re-offer property selling percentage				92.50%
Worldwide Plaza [Member] \| SL Green Realty Corp. and RXR Realty LLC [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage		48.70%
Liquidation value of property		$ 1,725.0
Worldwide Plaza [Member] \| Nomura Holdings America Inc [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of total annualized rental income				57.20%
Percentage of total cash rental income	58.50%
Mezzanine First Loan [Member] \| Worldwide Plaza [Member]
Schedule of Equity Method Investments [Line Items]
Subsidiary borrowings loan amount						$ 190.0
Liquidation Value [Member] \| Worldwide Plaza [Member]
Schedule of Equity Method Investments [Line Items]
Ownership percentage			98.80%
Liquidation Value [Member] \| Worldwide Plaza [Member] \| Nomura Holdings America Inc [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of total annualized rental income				35.80%	29.20%
Liquidation Value [Member] \| Worldwide Plaza [Member] \| Cravath Swaine Moore LLP [Member]
Schedule of Equity Method Investments [Line Items]
Percentage of total annualized rental income				39.10%	51.30%