Nature of Business and Summary of Significant Accounting Policies - Intangible Assets (Details) - USD ($)	1 Months Ended	3 Months Ended	12 Months Ended
	Aug. 31, 2008	Jun. 30, 2020	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2020
Intangible assets
Impairment of intangible asset					$ 1,852,000
Amortization expense			$ 391,000	$ 425,000	264,000
Changes in intangible assets
Carrying value		$ 13,848,000	13,848,000	13,848,000	13,848,000
Accumulated amortization		(8,732,000)	(9,548,000)	(9,157,000)	(8,732,000)
Net book value		5,116,000	4,300,000	$ 4,691,000	5,116,000
Future amortization expense
2023			361,000
2024			336,000
2025			315,000
2026			297,000
2027			$ 283,000
Weighted average remaining period			16 years 2 months 12 days	16 years 10 months 24 days
Customer relationships [Member]
Changes in intangible assets
Carrying value		9,800,000	$ 9,800,000	$ 9,800,000	9,800,000
Accumulated amortization		(8,732,000)	(9,143,000)	(8,955,000)	(8,732,000)
Net book value		1,068,000	657,000	845,000	1,068,000
Trade name
Changes in intangible assets
Carrying value		4,048,000	4,048,000	4,048,000	4,048,000
Accumulated amortization			(405,000)	(202,000)
Net book value		4,048,000	$ 3,643,000	$ 3,846,000	$ 4,048,000
G. Marks Hardware, Inc. | Customer relationships [Member]
Intangible assets
Useful life	20 years
G. Marks Hardware, Inc. | Trade name
Intangible assets
Impairment of intangible asset		$ 1,852,000
Useful life		20 years