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DEBT - Schedule of Debt Obligations (Details) € in Thousands, $ in Thousands	Mar. 31, 2024 USD ($)	Mar. 31, 2024 EUR (€)	Dec. 31, 2023 USD ($)	Dec. 31, 2023 EUR (€)	Sep. 13, 2022 USD ($)	Feb. 11, 2022 USD ($)
Debt Instrument [Line Items]
Aggregate Principal Committed	$ 2,420,000		$ 2,420,000
Outstanding Principal	1,492,257		1,502,263
Unused Portion	923,745		917,484
BNP Funding Facility \| Line of Credit
Debt Instrument [Line Items]
Aggregate Principal Committed	600,000		600,000
Outstanding Principal	300,000		282,000
Unused Portion	300,000		318,000
Truist Credit Facility \| Line of Credit
Debt Instrument [Line Items]
Aggregate Principal Committed	1,120,000	€ 238	1,120,000	€ 238
Outstanding Principal	492,257		520,263
Unused Portion	623,745		599,484
Outstanding letters of credit	3,998		253
2027 Notes \| Senior Notes
Debt Instrument [Line Items]
Aggregate Principal Committed	425,000		425,000			$ 425,000
Outstanding Principal	425,000		425,000
Unused Portion	0		0
Unamortized debt issuance costs	3,219		3,499
Unamortized original issuance discount	614		667
2025 Notes \| Senior Notes
Debt Instrument [Line Items]
Aggregate Principal Committed	275,000		275,000		$ 275,000
Outstanding Principal	275,000		275,000
Unused Portion	0		0
Unamortized debt issuance costs	1,763		2,065
Unamortized original issuance discount	$ 0		$ 0