KWE Unsecured Bonds - Additional Information (Details) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 USD ($)	Jun. 30, 2022 USD ($)	Jun. 30, 2023 EUR (€)	Dec. 31, 2022 USD ($)
Debt Instrument [Line Items]
Unrealized foreign currency translation gain	$ (11.7)	$ 60.3	$ (25.8)	$ 88.3
KWE
Debt Instrument [Line Items]
Unrealized foreign currency translation gain			$ 16.8
KWE | KWE unsecured bonds
Debt Instrument [Line Items]
Maximum percentage of total assets	60.00%		60.00%		60.00%
Maximum ratio of consolidated secured indebtedness to total assets	50.00%		50.00%		50.00%
Interest coverage ratio	1.50		1.50		1.50
Maximum ratio of unencumbered assets to unsecured indebtedness	125.00%		125.00%		125.00%
KWE | KWE unsecured bonds | KWE Euro Medium Term Note Programme
Debt Instrument [Line Items]
Debt face value	$ 518.3		$ 518.3		€ 475,000,000
Mortgage debt (excluding loan fees)	$ 517.1		$ 517.1			$ 507.1
Annual fixed coupon rate	3.25%		3.25%		3.25%