Nature of Business and Summary of Significant Accounting Policies - Intangible Assets (Details) - USD ($)	12 Months Ended
Jun. 30, 2023	Jun. 30, 2022	Jun. 30, 2021
Intangible assets
Amortization expense	$ 361,000	$ 391,000	$ 425,000
Changes in intangible assets
Carrying value	13,848,000	13,848,000	13,848,000
Accumulated amortization	(9,909,000)	(9,548,000)	(9,157,000)
Net book value	3,939,000	$ 4,300,000	4,691,000
Future amortization expense
2024	336,000
2025	315,000
2026	297,000
2027	283,000
2027	$ 269,000
Weighted average remaining period	15 years 6 months	16 years 2 months 12 days
Customer relationships
Changes in intangible assets
Carrying value	$ 9,800,000	$ 9,800,000	9,800,000
Accumulated amortization	(9,302,000)	(9,143,000)	(8,955,000)
Net book value	498,000	657,000	845,000
Trade name
Changes in intangible assets
Carrying value	4,048,000	4,048,000	4,048,000
Accumulated amortization	(607,000)	(405,000)	(202,000)
Net book value	$ 3,441,000	$ 3,643,000	$ 3,846,000

Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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The aggregate expense charged against earnings to allocate the cost of intangible assets (nonphysical assets not used in production) in a systematic and rational manner to the periods expected to benefit from such assets. As a noncash expense, this element is added back to net income when calculating cash provided by or used in operations using the indirect method.

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Accumulated amount of amortization of assets, excluding financial assets and goodwill, lacking physical substance with a finite life.

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-Topic 210
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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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Amount of amortization for assets, excluding financial assets and goodwill, lacking physical substance with finite life expected to be recognized in second fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach).

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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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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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Amount before accumulated amortization of intangible assets, excluding goodwill.

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Sum of the carrying amounts of all intangible assets, excluding goodwill, as of the balance sheet date, net of accumulated amortization and impairment charges.

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