BORROWINGS - Narrative (Details) - USD ($)				1 Months Ended			3 Months Ended		9 Months Ended		12 Months Ended
	Oct. 01, 2025	Jul. 28, 2025	Feb. 02, 2024	Jun. 30, 2025	Apr. 30, 2025	Oct. 31, 2022	Sep. 30, 2025	Sep. 30, 2024	Sep. 30, 2025	Sep. 30, 2024	Dec. 31, 2024	Feb. 28, 2025	Nov. 30, 2024	Oct. 01, 2024	Feb. 01, 2024
Debt Instrument [Line Items]
Loss from extinguishment of debt							$ 24,961,000	$ 200,000	$ 25,457,000	$ 200,000
Average remaining contractual maturities of the repurchase agreements									90 days		90 days
Master Agreements
Debt Instrument [Line Items]
Outstanding borrowings							$ 68,400,000		$ 68,400,000		$ 144,000,000
Weighted average interest rate on long-term debt outstanding							12.00%		12.00%		15.00%
Loan and Security Agreement
Debt Instrument [Line Items]
Outstanding borrowings							$ 63,200,000		$ 63,200,000
Long-term debt
Debt Instrument [Line Items]
Outstanding borrowings							487,789,000		487,789,000		$ 321,317,000
Long-term debt | Revolving Credit Facility
Debt Instrument [Line Items]
Loss from extinguishment of debt							23,900,000
Line of credit facility, maximum borrowing capacity												$ 58,000,000	$ 50,000,000
Increase in maximum principal amount												$ 8,000,000	15,000,000
Line of credit facility, remaining borrowing capacity							41,400,000		41,400,000		25,700,000
Long-term debt | Secured borrowing
Debt Instrument [Line Items]
Repaid of secured borrowings							153,900,000
Loss from extinguishment of debt							1,100,000
Long-term debt | Letter of Credit
Debt Instrument [Line Items]
Outstanding borrowings							16,600,000		16,600,000		24,300,000
Long-term debt | Loan and Security Agreement | Capitalized Interest Amounts Facility
Debt Instrument [Line Items]
Debt instrument, term					24 months
Line of credit facility, maximum borrowing capacity					$ 24,000,000
Floor rate					1.00%
Long-term debt | Loan and Security Agreement | Capitalized Interest Amounts Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					4.00%
Long-term debt | Loan and Security Agreement | Accrued Loan Purchasing Fee Receivables Facility
Debt Instrument [Line Items]
Debt instrument, term				30 months
Line of credit facility, maximum borrowing capacity				$ 65,000,000
Floor rate					1.00%
Long-term debt | Loan and Security Agreement | Accrued Loan Purchasing Fee Receivables Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate					1.90%
Long-term debt | SVB Receivables Facility
Debt Instrument [Line Items]
Outstanding borrowings											31,900,000
Debt instrument, term				3 years
Floor rate						0.00%
Debt instrument, basis spread on variable rate						3.50%
Long-term debt | The Credit Agreement | Revolving Credit Facility
Debt Instrument [Line Items]
Debt instrument, term			5 years
Line of credit facility, maximum borrowing capacity			$ 35,000,000												$ 25,000,000
Floor rate			1.00%
Debt instrument, base rate floor			2.00%
Long-term debt | The Credit Agreement | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR)
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			7.50%
Long-term debt | The Credit Agreement | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR) | Subsequent Event
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	7.50%
Long-term debt | The Credit Agreement | Revolving Credit Facility | Base Rate
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate			6.50%
Long-term debt | The Credit Agreement | Secured borrowing
Debt Instrument [Line Items]
Debt instrument, term			5 years
Line of credit facility, maximum borrowing capacity			$ 255,000,000										355,000,000
Increase in maximum principal amount													$ 100,000,000
Long-term debt | Revolving Credit Facility 2025 | Revolving Credit Facility | Subsequent Event
Debt Instrument [Line Items]
Debt instrument, term	3 years
Line of credit facility, maximum borrowing capacity	$ 132,000,000
Debt instrument, base rate floor	1.00%
Adjusted rate of SOFR	0.0100
Line of credit facility, commitment fee percentage	0.25%
Long-term debt | Revolving Credit Facility 2025 | Revolving Credit Facility | Secured Overnight Financing Rate (SOFR) | Subsequent Event
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	3.50%
Long-term debt | Revolving Credit Facility 2025 | Revolving Credit Facility | Base Rate | Subsequent Event
Debt Instrument [Line Items]
Debt instrument, basis spread on variable rate	2.50%
Exchangeable notes
Debt Instrument [Line Items]
Outstanding borrowings							148,148,000		148,148,000		$ 146,342,000
Exchangeable notes | Exchangeable Notes
Debt Instrument [Line Items]
Debt instrument, face amount														$ 160,000,000
Stated interest rate														6.125%
Debt issuance costs														$ (6,200,000)
Interest expense, debt							3,100,000		9,200,000
Debt issuance costs amortization							$ (600,000)		$ (1,800,000)
Debt instrument, interest rate, effective percentage							8.70%		8.70%
Senior Notes
Debt Instrument [Line Items]
Debt instrument, face amount		$ 500,000,000
Stated interest rate		8.875%
Interest expense, debt							$ 8,300,000
Debt issuance costs amortization							$ (400,000)
Redemption price, percentage (as a percent)		100.00%