FAIR VALUE OF FINANCIAL INSTRUMENTS - Quantitative Information (Details) - USD ($) $ in Thousands	9 Months Ended
Jun. 30, 2026	Sep. 30, 2025
Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 0	$ 0
Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	5,023,814	4,599,269
Level 3 \| Valuation, Market Approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 49,087	32,321
Level 3 \| Valuation, Market Approach \| Minimum \| Measurement Input, Appraised Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	3.00%
Level 3 \| Valuation, Market Approach \| Maximum \| Measurement Input, Appraised Value
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	51.00%
Nonrecurring \| Commercial finance
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 49,087	32,321
Nonrecurring \| Commercial finance \| Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Commercial finance \| Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Commercial finance \| Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 49,087	$ 32,321

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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