Investments in Unconsolidated Entities - Narrative (Details) - USD ($)	3 Months Ended	9 Months Ended
Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2020
Schedule of Equity Method Investments [Line Items]
Equity in income of unconsolidated entities	$ 313,000	$ 4,000	$ 424,000	$ 138,000
Impairment of unconsolidated entity investments	0	$ 0	0	$ 0
Financial Guarantee
Schedule of Equity Method Investments [Line Items]
Outstanding guarantees	$ 0		$ 0		$ 0

Equity Method Investments, Impairment Of Unconsolidated Entity Investments, Continuing Operations

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The current carrying amount of the liability for the freestanding or embedded guarantor's obligations under the guarantee or each group of similar guarantees.

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Amount of income (loss) for proportionate share of equity method investee's income (loss).

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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.

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