LOANS AND LEASES, NET - Narrative and Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Accounts, Notes, Loans and Financing Receivable [Line Items]
Foreclosed real estate and repossessed assets	$ 31,548		$ 31,638
Accrued Purchases of Available-For-Sale Securities, Not Paid	39,452	$ 0
Increase in loans held for sale	$ (6,571)	0
Percentage of specific allowance for losses	100.00%
Annual cap of ARM loans	2.00%
Lifetime cap of ARM loans	6.00%
Loans and Leases Receivable, Net Amount	$ 3,308,208		$ 2,931,699
Proceeds from sales	22,611	0
Gain (Loss) on Sales of Loans, Net	550	0
Payments to Acquire Loans Receivable	122,668	75,163
Proceeds from Sales	378	$ 5,916
Financing Receivable [Member] \| SBA/USDA [Member]
Accounts, Notes, Loans and Financing Receivable [Line Items]
Increase in loans held for sale	$ 7,500

Cash outflow for purchase of available-for-sale securities.

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- Definition

A clause stipulated in the contract of an adjustable-rate mortgage (ARM) that limits the possible increase in the loan's interest rate to a certain amount each year. The cap is usually defined in terms of rate, but the dollar amount of the principal and interest payment can be capped as well. Annual caps are designed to protect borrowers against a sudden and excessive increase in the amount of their monthly payments when rates rise sharply over a short period of time.

+ References

No definition available.

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- Definition

Represents an adjustable rate that limits the possible increase in the loan's interest rate to a certain amount over lifetime of the contract. The cap is usually defined in terms of rate, but the dollar amount of the principal and interest payment can be capped as well. These caps (limits) are designed to protect borrowers against a sudden and excessive increase in the amount of their periodic payments when rates rise sharply over a short period of time.

+ References

No definition available.

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- Definition

Refers to the percentage of specific allowance for loan losses specifically for those assets which have been classified as "loss".

+ References

No definition available.

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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

The net gain (loss) resulting from a sale of loans, including adjustments to record loans classified as held-for-sale at the lower-of-cost-or-market and fair value adjustments to loan held for investment purposes.

+ References

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- Definition

The increase (decrease) during the reporting period in the value of loans or securitized loans that are held with the intention to sell in the near future.

+ References

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- Definition

Amount after allowance and 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 and loans held for sale.

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- Definition

The cash outflow for the purchase of loan receivable arising from the financing of goods and services.

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- Definition

The cash inflow associated with the sale of loans receivables arising from the financing of goods and services.

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- Definition

The cash inflow from sales of loans that are secured with real estate mortgages and are held with the intention to resell in the near future.

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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.

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