Nature of Business and Summary of Significant Accounting Policies - Intangible Assets (Details) - USD ($)	3 Months Ended		12 Months Ended
	Sep. 30, 2021	Sep. 30, 2020	Jun. 30, 2021
Intangible assets
Impairment of intangible asset			$ 1,852,000
Useful life			20 years
Amortization expense	$ 98,000	$ 106,000
Changes in intangible assets
Carrying value	13,848,000		$ 13,848,000
Accumulated amortization	(9,255,000)		(9,157,000)
Net book value	4,593,000		$ 4,691,000
Future amortization expense
2022	390,000
2023	361,000
2024	336,000
2025	315,000
2026	$ 297,000
Weighted average period	16 years 8 months 12 days		16 years 10 months 24 days
Customer relationships
Changes in intangible assets
Carrying value	$ 9,800,000		$ 9,800,000
Accumulated amortization	(9,002,000)		(8,955,000)
Net book value	798,000		845,000
Trade name
Changes in intangible assets
Carrying value	4,048,000		4,048,000
Accumulated amortization	(253,000)		(202,000)
Net book value	$ 3,795,000		$ 3,846,000