LOANS AND LEASES, NET - Summary of Loans (Details) - USD ($) $ in Thousands	Dec. 31, 2024	Sep. 30, 2024	Dec. 31, 2023	Sep. 30, 2023
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	$ 4,565,947	$ 4,071,071
Net deferred loan origination costs (fees)	(3,266)	4,124
Total gross loans and leases	4,562,681	4,075,195
Allowance for credit losses	(74,337)	(71,765)
Total loans and leases, net	4,488,344	4,003,430
National Lending \| Term lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	1,735,539	1,554,641
Allowance for credit losses	(29,925)	(30,394)	$ (27,013)	$ (25,686)
National Lending \| Asset-based lending
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	608,261	471,897
Allowance for credit losses	(1,762)	(1,356)	(1,370)	(2,738)
National Lending \| Factoring
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	364,477	362,295
Allowance for credit losses	(5,765)	(5,757)	(7,433)	(6,566)
National Lending \| Lease financing
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	138,305	152,174
Allowance for credit losses	(881)	(1,189)	(4,008)	(3,302)
National Lending \| SBA/USDA
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	595,965	568,628
Allowance for credit losses	(3,807)	(3,273)	(3,289)	(2,962)
National Lending \| Other commercial finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	174,097	185,964
Allowance for credit losses	(421)	(607)	(3,312)	(3,089)
National Lending \| Commercial finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	3,616,644	3,295,599
Allowance for credit losses	(42,561)	(42,576)	(48,548)	(46,980)
National Lending \| Consumer finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	280,001	248,800
Allowance for credit losses	(30,361)	(28,669)	(41,635)	(49,496)
National Lending \| Tax services
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	45,051	8,825
Allowance for credit losses	(790)	(2)	(507)	(2)
National Lending \| Warehouse finance
Accounts, Notes, Loans and Financing Receivable [Line Items]
Total loans and leases	624,251	517,847
Allowance for credit losses	$ (625)	$ (518)	$ (350)	$ (377)

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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