Commitments and Contingencies (Details) $ in Thousands	12 Months Ended
Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)
Commitments and Contingencies Disclosure [Abstract]
Reserve for unfunded loan commitments	$ 384	$ 241
Employee severance compensation plan, employee minimum service requirement (in years)	2 years
Employee severance compensation plan, period following effective date of a change in company control (in months)	12 months
Employee severance compensation plan, eligible payment, maximum compensation term (in months)	18 months
Employee severance compensation plan, annual compensation multiplier	2.99
Employee severance compensation plan, period following effective date of change in control for eligible severance benefits (in years)	5 years

Employee Severance Compensation Plan, Annual Compensation Multiplier

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Employee Severance Compensation Plan, Eligible Payment, Maximum Compensation Term

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Employee Severance Compensation Plan, Employee Service Requirement

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Employee Severance Compensation Plan, Period Following Effective Date Of A Change In Company Control

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Employee Severance Compensation Plan, Period Following Effective Date Of Change In Control For Eligible Severance Benefits

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