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Borrowings - Additional information (Details) € in Millions, £ in Millions, kr in Millions				1 Months Ended	12 Months Ended
	Nov. 05, 2024 USD ($)	Feb. 07, 2024 USD ($)	Nov. 23, 2021 USD ($)	Feb. 28, 2019 USD ($)	Dec. 31, 2024 SEK (kr)	Dec. 31, 2023 SEK (kr)	Dec. 31, 2024 USD ($)	Dec. 31, 2024 GBP (£)	Dec. 31, 2024 EUR (€)	Feb. 12, 2024 USD ($)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 GBP (£)	Dec. 31, 2023 EUR (€)	Apr. 30, 2022 USD ($)	Apr. 01, 2022 USD ($)	Feb. 25, 2022 USD ($)	Nov. 04, 2021 USD ($)	Feb. 25, 2021 USD ($)	Nov. 04, 2020 USD ($)	Sep. 29, 2020 USD ($)	Sep. 24, 2020 USD ($)	Aug. 03, 2020 USD ($)
Debt Instrument [Line Items]
Borrowings under credit facilities							$ 438,590,000				$ 719,914,000
February 21, 2019 | Line of Credit
Debt Instrument [Line Items]
Commitment aggregate amount	$ 825,000,000			$ 800,000,000			$ 800,000,000				1,065,000,000				$ 1,065,000,000	$ 965,000,000	$ 875,000,000
Line of credit facility commitment aggregate value				$ 1,200,000,000											$ 1,500,000,000	$ 1,500,000,000
Line of credit, repayment period after maturity					1 year
Debt instrument, basis spread on variable rate	1.875%			2.25%
Change in reallocation of commitments	$ 100,000,000
Debt instrument, basis spread on variable rate, floor				1.00%
Unused capacity, commitment fee percentage				0.375%
Debt issuance costs incurred				$ 6,400,000										$ 10,700,000
Debt instrument, basis spread on variable rate					6.037%		6.037%	6.037%	6.037%
February 21, 2019 | Line of Credit | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 438,600,000				719,100,000
February 21, 2019 | Line of Credit | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.875%
February 21, 2019 | Line of Credit | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.875%
February 21, 2019 | Line of Credit | Applicable Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.875%
February 21, 2019 | Line of Credit | Screen Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.0875%
February 21, 2019 | Line of Credit | Federal Funds Purchased
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.50%
February 21, 2019 | Line of Credit | Overnight Bank Funding Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				0.50%
February 21, 2019 | Line of Credit | One-Month Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				1.00%
Debt instrument, credit spread adjustment				0.0010
February 21, 2019 | Line of Credit | Interest Period Of One Month
Debt Instrument [Line Items]
Debt instrument, credit spread adjustment	0.0010			0.0010
February 21, 2019 | Line of Credit | Interest Period Of Three Month
Debt Instrument [Line Items]
Debt instrument, credit spread adjustment				0.0015
February 21, 2019 | Line of Credit | Interest Period Of Six Month
Debt Instrument [Line Items]
Debt instrument, credit spread adjustment				0.0025
February 21, 2019 | Line of Credit | External Credit Rating, Investment Grade
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate				2.00%
Debt Denominated In U.S Dollars | Line of Credit
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate						5.328%
Borrowings under credit facilities							$ 237,000,000.0				$ 489,500,000
Debt instrument, basis spread on variable rate					6.484%	7.428%	6.484%	6.484%	6.484%		7.428%	7.428%	7.428%
Debt Denominated In U.S Dollars | Line of Credit | One-Month Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					4.509%
Debt Denominated In Swedish Kronas | Line of Credit
Debt Instrument [Line Items]
Borrowings under credit facilities					kr 9.8	kr 12.8	$ 900,000				$ 1,300,000
Debt instrument, basis spread on variable rate					4.625%	6.063%	4.625%	4.625%	4.625%		6.063%	6.063%	6.063%
Debt Denominated In Swedish Kronas | Line of Credit | Stockholm Interbank Offered Rate (STIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					2.75%	4.063%
Debt Denominated In British Pounds | Line of Credit
Debt Instrument [Line Items]
Borrowings under credit facilities							$ 69,600,000	£ 55.6			$ 84,900,000	£ 66.6
Debt instrument, basis spread on variable rate					6.608%	7.22%	6.608%	6.608%	6.608%		7.22%	7.22%	7.22%
Debt Denominated In British Pounds | Line of Credit | Sterling Overnight Index Average (SONIA)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					4.70%
Debt Denominated In British Pounds | Line of Credit | GBP LIBOR
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate						5.22%
Debt Denominated In Euro | Line of Credit
Debt Instrument [Line Items]
Borrowings under credit facilities							$ 131,100,000		€ 126.6		$ 144,300,000		€ 130.6
Debt instrument, basis spread on variable rate					4.938%	5.875%	4.938%	4.938%	4.938%		5.875%	5.875%	5.875%
Debt Denominated In Euro | Line of Credit | Euro Interbank Offered Rate (EURIBOR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					3.063%	3.875%
September 24, 2020 - August 2025 Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount																				$ 25,000,000	$ 25,000,000	$ 50,000,000
Fixed interest rate					4.66%		4.66%	4.66%	4.66%													4.66%
Ownership percent for immediate conversion					66.67%		66.67%	66.67%	66.67%
September 24, 2020 - August 2025 Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 49,500,000				$ 47,800,000
November 5, 2020 - Series B Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount																			$ 62,500,000
Fixed interest rate					4.25%		4.25%	4.25%	4.25%										4.25%
Ownership percent for immediate conversion					66.67%		66.67%	66.67%	66.67%
November 5, 2020 - Series B Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 61,600,000				59,300,000
November 5, 2020 - Series C Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount																			$ 112,500,000
Fixed interest rate					4.75%		4.75%	4.75%	4.75%										4.75%
November 5, 2020 - Series C Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 108,300,000				102,500,000
Series B And Series C Senior Unsecured Notes Due November | Notes
Debt Instrument [Line Items]
Interest rate extended																			0.0075
Investment grade conditions																			0.0150
February 25, 2021 Series D Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount																		$ 80,000,000
Fixed interest rate					3.41%		3.41%	3.41%	3.41%									3.41%
Ownership percent for immediate conversion					66.67%		66.67%	66.67%	66.67%
February 25, 2021 Series D Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 77,300,000				73,400,000
February 25, 2021 Series E Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount																		$ 70,000,000
Fixed interest rate					4.06%		4.06%	4.06%	4.06%									4.06%
Ownership percent for immediate conversion					66.67%		66.67%	66.67%	66.67%
February 25, 2021 Series E Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 65,400,000				61,200,000
Series D And Series E Senior Unsecured Notes Due February | Notes
Debt Instrument [Line Items]
Interest rate extended																		0.0075
Investment grade conditions																		0.0150
November 23, 2021 - November 2026 Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount			$ 350,000,000
Fixed interest rate			3.30%		3.30%		3.30%	3.30%	3.30%
Redemption percentage			100.00%
November 23, 2021 - November 2026 Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 329,300,000				$ 311,400,000
February 12, 2024 - February 2029 Notes | Interest Rate Swap
Debt Instrument [Line Items]
Notional Amount										$ 300,000,000
Company Receives										7.00%
Derivative liabilities							$ (4,400,000)
February 12, 2024 - February 2029 Notes | Secured Overnight Financing Rate (SOFR) Overnight Index Swap Rate | Interest Rate Swap
Debt Instrument [Line Items]
Derivative, variable interest rate										3.1475%
February 12, 2024 - February 2029 Notes | Notes
Debt Instrument [Line Items]
Aggregate principal amount		$ 300,000,000
Fixed interest rate		7.00%			7.00%		7.00%	7.00%	7.00%
Redemption percentage		100.00%
Proceeds from issuance of senior long term debt, net		$ 292,900,000
February 12, 2024 - February 2029 Notes | Notes | Level 3
Debt Instrument [Line Items]
Debt fair value							$ 295,600,000

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