FAIR VALUE OF FINANCIAL INSTRUMENTS - Quantitative Information (Details) $ in Thousands	3 Months Ended
Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)
Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	15.00%
Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	59.00%
Valuation, Market Approach \| Minimum \| Discount Rate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Measurement input	0.04
Valuation, Market Approach \| Maximum \| Discount Rate
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Measurement input	0.35
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	3,484,705	3,525,803
Total loans and leases, net individually evaluated for credit loss \| Level 3 \| Valuation, Market Approach
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 8,544	1,575
Total loans and leases, net individually evaluated for credit loss \| Level 3 \| Valuation, Market Approach \| Minimum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	15.00%
Total loans and leases, net individually evaluated for credit loss \| Level 3 \| Valuation, Market Approach \| Maximum
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Range of estimated selling cost (percentage)	59.00%
Nonrecurring
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	$ 8,544	1,576
Nonrecurring \| Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	8,544	1,576
Nonrecurring \| Commercial finance
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	8,544	1,575
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	8,544	1,575
Nonrecurring \| Total loans and leases, net individually evaluated for credit loss
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	8,544	1,575
Nonrecurring \| Total loans and leases, net individually evaluated for credit loss \| Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Total loans and leases, net individually evaluated for credit loss \| Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	0	0
Nonrecurring \| Total loans and leases, net individually evaluated for credit loss \| Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Fair value	8,544	1,575
Nonrecurring \| Foreclosed assets, net
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Foreclosed assets, net	0	1
Nonrecurring \| Foreclosed assets, net \| Level 1
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Foreclosed assets, net	0	0
Nonrecurring \| Foreclosed assets, net \| Level 2
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Foreclosed assets, net	0	0
Nonrecurring \| Foreclosed assets, net \| Level 3
Fair Value Inputs, Assets, Quantitative Information [Line Items]
Foreclosed assets, net	$ 0	$ 1

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No definition available.

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- Definition

Value of input used to measure alternative investment.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI https://asc.fasb.org/extlink&oid=126976982&loc=d3e19207-110258

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- Definition

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.

+ References

No definition available.

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- Definition

Fair value portion of loan receivable, including, but not limited to, mortgage loans held for investment, finance receivables held for investment, policy loans on insurance contracts.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-URI https://asc.fasb.org/subtopic&trid=2196772

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- Definition

Carrying amount as of the balance sheet date of land and buildings obtained through foreclosure proceedings or defeasance in full or partial satisfaction of a debt arrangement.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 50
-Paragraph 11
-URI https://asc.fasb.org/extlink&oid=123577603&loc=d3e5162-111524

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 10
-Section 45
-Paragraph 3
-URI https://asc.fasb.org/extlink&oid=124259787&loc=d3e4437-111522

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