Debt - Summary of Senior Unsecured Credit Facility (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Senior Unsecured Credit Facility
Debt outstanding	$ 780,048	$ 722,075
Unamortized discount	29,198
Unsecured Revolving Credit Facility:
Senior Unsecured Credit Facility
Debt outstanding	476,085	410,596
Unsecured Revolving Credit Facility: | EUR
Senior Unsecured Credit Facility
Debt outstanding	$ 283,076	205,001
Unsecured Revolving Credit Facility: | EUR | EURIBOR
Senior Unsecured Credit Facility
Variable interest rate (percentage)	0.85%
Unsecured Revolving Credit Facility: | GBP
Senior Unsecured Credit Facility
Debt outstanding	$ 173,217	184,660
Unsecured Revolving Credit Facility: | GBP | GBP LIBOR
Senior Unsecured Credit Facility
Variable interest rate (percentage)	0.8826%
Unsecured Revolving Credit Facility: | JPY
Senior Unsecured Credit Facility
Debt outstanding	$ 19,792	20,935
Unsecured Revolving Credit Facility: | JPY | JPY LIBOR
Senior Unsecured Credit Facility
Variable interest rate (percentage)	0.85%
Unsecured Term Loans:
Senior Unsecured Credit Facility
Debt outstanding	$ 303,963	311,479
Unsecured Term Loans: | EUR
Senior Unsecured Credit Facility
Debt outstanding	$ 107,125	109,296
Unsecured Term Loans: | EUR | EURIBOR
Senior Unsecured Credit Facility
Variable interest rate (percentage)	0.95%
Unsecured Term Loans: | GBP
Senior Unsecured Credit Facility
Debt outstanding	$ 196,838	202,183
Unamortized discount	$ 800	$ 900
Unsecured Term Loans: | GBP | GBP LIBOR
Senior Unsecured Credit Facility
Variable interest rate (percentage)	0.9826%