LOANS AND LEASES, NET - Direct Financing and Sales-type Leases, and Lease Receivable Maturity (Details) - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Loans and Leases Receivable Disclosure [Abstract]
Carrying Amount	$ 299,487	$ 191,733
Unguaranteed residual assets	17,203	13,353
Unamortized initial direct costs	2,078	1,790
Unearned income	(35,606)	(27,171)
Total investment in direct financing and sales-type leases	283,162	$ 179,705
Interest income - loans and leases
Interest income on net investments in direct financing and sales-type leases	18,300
Lease income from operating lease payments	44,319
Profit (loss) recorded on commencement date on sales-type leases	2,152
Other	4,357
Total leasing and equipment finance noninterest income	50,828
Total lease income	69,128
Sales-type and Direct Financing Leases, Lease Receivable, Fiscal Year Maturity [Abstract]
2021	107,558
2022	87,775
2023	58,906
2024	33,059
2025	10,097
Thereafter	2,092
Total undiscounted future minimum lease payments receivable for direct financing and sales-type leases	299,487
Third-party residual value guarantees	0
Total carrying amount of direct financing and sales-type leases	$ 299,487

Direct Financing Lease, Unamortized Initial Direct Costs

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Leasing and Equipment Finance, Non-interest income

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Amount of deferred selling profit from direct financing lease.

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Amount of lease income from operating, direct financing, and sales-type leases. Includes, but is not limited to, variable lease payments, interest income, profit (loss) recognized at commencement, and lease payments paid and payable to lessor.

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Amount of net investment in sales-type and direct financing lease.

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Amount of operating lease income from lease payments paid and payable to lessor. Excludes variable lease payments not included in measurement of lease receivable.

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Amount of residual asset covered by residual value guarantee. Excludes guarantee considered to be lease payments for lessor.

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Amount of interest income from net investment in sales-type and direct financing leases.

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases.

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted cash flows to be received by lessor for sales-type and direct financing leases after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of undiscounted lease receivable in excess of discounted receivable for sales-type and direct financing leases.

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Present value of lease payments not yet received by lessor and amount expected to be derived from underlying asset, following end of lease term guaranteed by lessee or other third party unrelated to lessor, from sales-type lease.

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