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REVENUES - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2026	Sep. 30, 2025	Dec. 31, 2025	Dec. 31, 2024
Capitalized Contract Cost [Line Items]
Contract assets	$ 82,100	$ 76,200	$ 89,700	$ 101,800
Increase (decrease) in contract assets	(7,600)	(25,600)
Contract liability	2,700		5,100
Related Party
Capitalized Contract Cost [Line Items]
Contract assets	81,400	75,500	87,500	$ 100,800
OTHER ASSETS	83,762		89,509
Related Party \| Legacy Incentive Compensation Receivable
Capitalized Contract Cost [Line Items]
OTHER ASSETS	69,300		76,300
Related Party \| Performance Fee Contract Assets
Capitalized Contract Cost [Line Items]
OTHER ASSETS	11,500	8,900	$ 10,400
Related Party \| Great Park
Capitalized Contract Cost [Line Items]
Revenue from customers	13,400	$ 52,300
Related Party \| Great Park \| Legacy Incentive Compensation Receivable
Capitalized Contract Cost [Line Items]
Revenue from customers	4,500
Contract liability	$ 4,500