LOANS AND LEASES, NET - Past Due Loans (Details) - USD ($) $ in Thousands	Sep. 30, 2024	Sep. 30, 2023
Financing Receivable, Past Due [Line Items]
Loans and leases	$ 4,075,195	$ 4,366,116
Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	248,800	254,400
Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,800	5,200
Accruing and Nonaccruing Loans and Leases
Financing Receivable, Past Due [Line Items]
Loans and leases	4,759,941	4,437,460
Accruing and Nonaccruing Loans and Leases | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	4,071,071	4,359,681
Accruing and Nonaccruing Loans and Leases | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	688,870	77,779
Accruing and Nonaccruing Loans and Leases | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	1,554,641	1,308,133
Accruing and Nonaccruing Loans and Leases | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	471,897	382,371
Accruing and Nonaccruing Loans and Leases | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	362,295	358,344
Accruing and Nonaccruing Loans and Leases | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	152,174	183,392
Accruing and Nonaccruing Loans and Leases | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		800,077
Accruing and Nonaccruing Loans and Leases | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	568,628	524,750
Accruing and Nonaccruing Loans and Leases | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	185,964	166,091
Accruing and Nonaccruing Loans and Leases | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,295,599	3,723,158
Accruing and Nonaccruing Loans and Leases | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	248,800	254,416
Accruing and Nonaccruing Loans and Leases | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,825	5,192
Accruing and Nonaccruing Loans and Leases | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	517,847	376,915
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans and leases	29,609	27,052
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	27,343	26,426
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	2,266	626
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	19,776	13,898
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	3,605	6,865
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		2,159
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	0	512
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	23,381	23,434
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,962	2,992
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 30-59 Days Past Due | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans and leases	12,218	12,117
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	10,857	11,568
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	1,361	549
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	5,124	7,723
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	1,595	158
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		1,262
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	952	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	7,671	9,143
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,186	2,425
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | 60-89 Days Past Due | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans and leases	32,811	27,950
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	31,761	27,644
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	1,050	306
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	17,694	11,136
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	123
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	109	4,828
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		2,339
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	2,172	1,835
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	91
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	19,975	20,352
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,053	2,210
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,733	5,082
Accruing and Nonaccruing Loans and Leases | > 89 Days Past Due | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | Total Past Due
Financing Receivable, Past Due [Line Items]
Loans and leases	74,638	67,119
Accruing and Nonaccruing Loans and Leases | Total Past Due | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	69,961	65,638
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	4,677	1,481
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	42,594	32,757
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	123
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	5,309	11,851
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		5,760
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	3,124	2,347
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	91
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	51,027	52,929
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	10,201	7,627
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,733	5,082
Accruing and Nonaccruing Loans and Leases | Total Past Due | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Accruing and Nonaccruing Loans and Leases | Current
Financing Receivable, Past Due [Line Items]
Loans and leases	4,685,303	4,370,341
Accruing and Nonaccruing Loans and Leases | Current | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	4,001,110	4,294,043
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	684,193	76,298
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	1,512,047	1,275,376
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	471,897	382,248
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	362,295	358,344
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	146,865	171,541
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		794,317
Accruing and Nonaccruing Loans and Leases | Current | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	565,504	522,403
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	185,964	166,000
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,244,572	3,670,229
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	238,599	246,789
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	92	110
Accruing and Nonaccruing Loans and Leases | Current | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	517,847	376,915
Nonperforming Loans and Leases
Financing Receivable, Past Due [Line Items]
Loans and leases	41,562	56,212
Nonaccrual Balance	26,412	37,372
Nonperforming Loans and Leases | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	40,512	55,906
Nonaccrual Balance	26,412	37,372
Nonperforming Loans and Leases | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	1,050	306
Nonaccrual Balance	0	0
Nonperforming Loans and Leases | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	25,385	19,061
Nonaccrual Balance	23,462	15,324
Nonperforming Loans and Leases | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	18,082
Nonaccrual Balance	0	18,082
Nonperforming Loans and Leases | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	29	1,298
Nonaccrual Balance	29	1,298
Nonperforming Loans and Leases | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	806	5,908
Nonaccrual Balance	746	1,666
Nonperforming Loans and Leases | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		2,339
Nonaccrual Balance		0
Nonperforming Loans and Leases | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	2,506	1,835
Nonaccrual Balance	2,175	1,002
Nonperforming Loans and Leases | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	91
Nonaccrual Balance	0	0
Nonperforming Loans and Leases | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	28,726	48,614
Nonaccrual Balance	26,412	37,372
Nonperforming Loans and Leases | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,053	2,210
Nonaccrual Balance	0	0
Nonperforming Loans and Leases | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,733	5,082
Nonaccrual Balance	0	0
Nonperforming Loans and Leases | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Nonaccrual Balance	0	0
Nonperforming Loans and Leases | > 89 Days Past Due
Financing Receivable, Past Due [Line Items]
Loans and leases	15,150	18,840
Nonperforming Loans and Leases | > 89 Days Past Due | Total loans and leases held for investment
Financing Receivable, Past Due [Line Items]
Loans and leases	14,100	18,534
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Loans held for sale
Financing Receivable, Past Due [Line Items]
Loans and leases	1,050	306
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Term lending
Financing Receivable, Past Due [Line Items]
Loans and leases	1,923	3,737
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Asset-based lending
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Factoring
Financing Receivable, Past Due [Line Items]
Loans and leases	0	0
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Lease financing
Financing Receivable, Past Due [Line Items]
Loans and leases	60	4,242
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Insurance premium finance
Financing Receivable, Past Due [Line Items]
Loans and leases		2,339
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | SBA/USDA
Financing Receivable, Past Due [Line Items]
Loans and leases	331	833
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Other commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	0	91
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Commercial finance
Financing Receivable, Past Due [Line Items]
Loans and leases	2,314	11,242
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Consumer finance
Financing Receivable, Past Due [Line Items]
Loans and leases	3,053	2,210
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Tax services
Financing Receivable, Past Due [Line Items]
Loans and leases	8,733	5,082
Nonperforming Loans and Leases | > 89 Days Past Due | National Lending | Warehouse finance
Financing Receivable, Past Due [Line Items]
Loans and leases	$ 0	$ 0