Marketable Securities - Available-for-sale securities in a loss position (Details) - USD ($)	Jun. 30, 2024	Jun. 30, 2023
Available-for-sale securities in a loss position
Continuous Loss Position for 12 Months or More, Estimated Fair Value	$ 4,677,000	$ 4,457,000
Continuous Loss Position for 12 Months or More, Gross Unrealized Losses	486,000	537,000
Mutual funds
Available-for-sale securities in a loss position
Continuous Loss Position for 12 Months or More, Estimated Fair Value	4,677,000	4,457,000
Continuous Loss Position for 12 Months or More, Gross Unrealized Losses	$ 486,000	$ 537,000

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for more than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/exampleRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 55
-Paragraph 8
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479081/326-30-55-8

Reference 2: http://fasb.org/us-gaap/role/ref/otherTransitionRef
-Topic 320
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 7
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481800/320-10-50-7

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 326
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 5
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147479106/326-30-50-5

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