Related Party Transactions - Shared Services Agreement (Details) - TBCO - USD ($) $ in Thousands	12 Months Ended
Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018
Related Party Transaction [Line Items]
Payments for services and covenants	$ 618,000
Expense under shared services agreement	0	$ 155,000	$ 592,000
Due to related parties	$ 0	$ 0

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

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