Debt - Unsecured Revolving Credit and Term Loan Facilities (Details) - Unsecured term loan facility		12 Months Ended
	Mar. 19, 2020 USD ($) option	Dec. 31, 2021	Dec. 31, 2020	Mar. 31, 2020 USD ($)
Unsecured revolving credit facility and term loan
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 1,315,000,000
Unsecured revolving credit facility higher borrowing capacity option	1,750,000,000
Unsecured revolving credit facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 1,100,000,000
Outstanding borrowings				$ 550,000,000.0
Number of options to extend maturity | option	2
Extension period	6 months
Term loan facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	$ 215,000,000.0
Outstanding borrowings				215,000,000.0
Unsecured term loan facility
Line of Credit Facility [Line Items]
Maximum borrowing capacity	175,000,000
Unsecured revolving credit facility higher borrowing capacity option	$ 225,000,000
Outstanding borrowings				$ 175,000,000.0
Minimum | Unsecured revolving credit facility
Line of Credit Facility [Line Items]
Extension fee, as a percent of outstanding commitments under revolving credit facility	0.0625%
Maximum | Unsecured revolving credit facility
Line of Credit Facility [Line Items]
Extension fee, as a percent of outstanding commitments under revolving credit facility	0.075%
Forecast | Unsecured term loan facility
Line of Credit Facility [Line Items]
Prepayment fee, as a percent of principal amount prepaid		1.00%	2.00%