Carrying amount as of the balance sheet date of obligations due all related parties.

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Transactions with Related Parties (Details) - USD ($)	12 Months Ended
Transactions with Related Parties (Details) - USD ($)	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Related Party Transaction [Line Items]
Interest on related party notes payable	$ 0	$ 0	$ 0
National Australia Bank Limited \| Shares from former parent company \| Salaries and employee benefits
Related Party Transaction [Line Items]
Expenses from transactions with related party	0.0
National Australia Bank Limited \| Shares from former parent company \| Restricted shares \| Accrued expenses and other liabilities
Related Party Transaction [Line Items]
Due to related parties	$ 0.0	$ 0.0