Marketable Securities - Fair Value (Details)	12 Months Ended
Jun. 30, 2021 USD ($)
Marketable Securities:
Cost	$ 5,422,000
Fair Value	5,413,000
Unrealized Gain (Loss)	(9,000)
Transfers between levels 1 and 2	0
Transfers in or out of level 3	0
Fair Value, Inputs, Level 1
Marketable Securities:
Cost	5,422,000
Fair Value	5,413,000
Unrealized Gain (Loss)	$ (9,000)

Amount of transfers of marketable securities for level 3.

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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.

+ References

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Amount of transfers of liabilities measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
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- Definition

Amount of investment in marketable security, classified as current.

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section 45
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Amount of unrealized gain (loss) on investment in marketable security.

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-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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Amount of cash outflow for purchase of marketable security.

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