Related Party Transactions - Summary of Fees to Vornado (Detail) - Vornado - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Sep. 30, 2021	Sep. 30, 2020
Related Party Transaction [Line Items]
Fees to related party	$ 3,489	$ 2,075	$ 8,518	$ 6,247
Company management fees
Related Party Transaction [Line Items]
Fees to related party	700	700	2,100	2,100
Development fees
Related Party Transaction [Line Items]
Fees to related party	30	188	109	456
Leasing fees
Related Party Transaction [Line Items]
Fees to related party	1,291	113	1,730	172
Commission on sale of real estate
Related Party Transaction [Line Items]
Fees to related party	0	0	300	0
Property management, cleaning, engineering and security fees
Related Party Transaction [Line Items]
Fees to related party	$ 1,468	$ 1,074	$ 4,279	$ 3,519