Investments in Unconsolidated Entities - Narrative (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019	Sep. 30, 2019
Equity Method Investments and Joint Ventures [Abstract]
Impairment of unconsolidated entity investments	$ 0	$ 0	$ 0	$ 0
Schedule of Equity Method Investments [Line Items]
Equity in income of unconsolidated entities	4	299	138	316
Equity in income of unconsolidated entities	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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