Amount of allowance for credit loss on financing receivable. Excludes allowance for financing receivable covered under loss sharing agreement.

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Amount of undisbursed portion of the loan receivable balance (loans in process). Excludes loans and leases covered under loss sharing agreements.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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Commitment and Contingencies

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Commitment and Contingencies - Additional Information (Details) - USD ($) $ in Thousands	6 Months Ended
	Mar. 31, 2020	Dec. 31, 2019	Sep. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018
Commitment and Contingencies [Line Items]
Weighted average remaining lease term	8 years 10 months 24 days
Weighted average discount rate	2.00%
Operating lease payments	$ 3,178
Right-of-use assets obtained in exchange for lease liabilities	2,734
Loans in process	1,289,812		$ 1,201,341
Allowance for loan losses	139,501	$ 132,513	131,534	$ 133,086	$ 131,165	$ 129,257
Unfunded Loan Commitment
Commitment and Contingencies [Line Items]
Allowance for loan losses	8,500		6,900
Loans and Leases Receivable
Commitment and Contingencies [Line Items]
Loans in process	$ 2,646,603		$ 2,379,089