Debt - Summary of Outstanding Debt (Parenthetical) (Details) - USD ($) $ in Billions	6 Months Ended	12 Months Ended
	Jun. 30, 2021	Dec. 31, 2020
Credit Facility With Variable Rate [Member] | Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 1.0	$ 1.0
1633 Broadway [Member]
Debt Instrument [Line Items]
Ownership percentage of Property	90.00%	90.00%
One Market Plaza [Member]
Debt Instrument [Line Items]
Ownership percentage of Property	49.00%	49.00%
300 Mission Street [Member]
Debt Instrument [Line Items]
Ownership percentage of Property	31.10%	31.10%