Investments in Unconsolidated Entities - Narrative (Details) - USD ($)	3 Months Ended		6 Months Ended
	Mar. 31, 2021	Mar. 31, 2020	Mar. 31, 2021	Mar. 31, 2020	Sep. 30, 2020
Schedule of Equity Method Investments [Line Items]
Equity in income of unconsolidated entities	$ 186,000	$ 147,000	$ 111,000	$ 134,000
Impairment of unconsolidated entity investments	0	$ 0	0	$ 0
Financial Guarantee
Schedule of Equity Method Investments [Line Items]
Outstanding guarantees	$ 0		$ 0		$ 0