LOANS AND ALLOWANCE FOR LOAN LOSSES - Purchased Credit Impaired Loans (Details) - USD ($)	3 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Purchase credit impaired loans
Carrying value of the loan	$ 1,161,162,000	$ 1,143,575,000
Allowance for loan losses, collectively evaluated for impairment	6,011,000	5,162,000
Acquired with deteriorated credit quality
Purchase credit impaired loans
Carrying value of the loan	810,000	2,641,000
Acquired with deteriorated credit quality \| Consumer
Purchase credit impaired loans
Carrying value of the loan	810,000	2,600,000
Accretable yield	0	0
Allowance for loan losses, collectively evaluated for impairment	82,000	384,000
Interest income recognized	$ 118,000	$ 509,000	$ 2,100,000

Amount of the excess of a loan's cash flows expected to be collected over the investor's initial investment in acquired loans not accounted for as debt securities with evidence of deterioration of credit quality.

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 30
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- Definition

The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

+ References

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-Publisher FASB
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Amount of interest income recognized that the financing receivables (with related allowance for credit losses and without a related allowance for credit losses) were impaired.

+ References

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-Publisher FASB
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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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