LOANS AND LEASES, NET - Schedule of Loans Purchased and Sold, by Portfolio Segment (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2023	Dec. 31, 2022
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Purchased, Loans held for investment	$ 89,390	$ 67,649
Loans Sold, Loans held for sale	626,336	402,870
Loans Sold, Total sales	626,336	402,870
National Lending \| Warehouse finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Purchased, Loans held for investment	89,390	67,649
National Lending \| Commercial finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Sold, Loans held for sale	3,872	855
National Lending \| Consumer finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Loans Sold, Loans held for sale	$ 622,464	$ 402,015

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No definition available.

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The cash outflow from (a) purchases of loans held-for-investment, (b) purchases of leases held-for-investment, and (c) both.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 13
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-13

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The net cash inflow from (a) sales of loans held-for-investment, (b) sales of leases held-for-investment, and (c) both. Includes proceeds from securitizations of loans.

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-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
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-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482740/230-10-45-12

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The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 25
-Subparagraph (c)
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