Summary of Significant Accounting Policies - Fair Value Measurement (Details) - USD ($) $ in Millions	Sep. 30, 2024	Jun. 30, 2024
Assets and liabilities measured at fair value
Estimated fair value of long-term debt	$ 666.6
Estimated fair value of marketable securities	221.9
Measured on a recurring basis
Assets and liabilities measured at fair value
Assets, Fair Value Disclosure	0.0	$ 0.0
Liabilities, Fair Value Disclosure	$ 0.0	$ 0.0

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
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- Definition

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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (a)
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
-SubTopic 10
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-Paragraph 2
-Subparagraph (b)
-Publisher FASB
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Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 820
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-Paragraph 3
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-URI https://asc.fasb.org//1943274/2147482106/820-10-50-3

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- Definition

Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

+ References

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Fair value of financial and nonfinancial obligations.

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- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

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