Mortgages Payable - Summary of Mortgages Payable (Details) - Mortgages payable $ in Millions	9 Months Ended	12 Months Ended
	Sep. 30, 2023 USD ($) mortgage property	Dec. 31, 2022 USD ($) property mortgage
Debt
Number of properties | property	131	136
Weighted Average Stated Interest Rate (as a percent)	4.80%	4.80%
Weighted Average Effective Interest Rate (as a percent)	3.30%	3.30%
Weighted Average Remaining Years Until Maturity	8 months 12 days	1 year 4 months 24 days
Remaining Principal Balance	$ 822.0	$ 842.3
Unamortized Premium and Deferred Financing Costs Balance, net	2.3	11.6
Mortgage Payable Balance	$ 824.2	$ 853.9
Number of mortgages | mortgage	16	18
Number of Sterling-denominated mortgages paid quarterly | mortgage	1	1
Minimum
Debt
Weighted Average Effective Interest Rate (as a percent)	1.30%	2.70%
Stated interest rate (as a percent)	3.00%	3.00%
Maximum
Debt
Weighted Average Effective Interest Rate (as a percent)	6.60%	6.60%
Stated interest rate (as a percent)	6.90%	6.90%