Income Taxes - Additional Information (Details) - USD ($) $ in Millions	12 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2024
Income Taxes [Line Items]
Effective tax rates (as a percent)	(11.00%)	22.00%	(10.00%)
Change in valuation allowance	$ (48.2)	$ 9.3	$ 15.0
Operating loss carryforwards, subject to expiration	739.8
Penalties and interest	0.0	$ 0.0	$ 0.0
Domestic Tax Jurisdiction
Income Taxes [Line Items]
Net operating loss carryforwards	1,000.0
Research and development tax credit carryforwards	99.0
State Tax
Income Taxes [Line Items]
Net operating loss carryforwards	847.8
Research and development tax credit carryforwards	$ 67.6

Income Taxes [Line Items]

No definition available.

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- Definition

Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are subject to expiration dates.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 6
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-6

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- Definition

Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482685/740-10-50-12

Reference 2: http://www.xbrl.org/2003/role/exampleRef
-Topic 740
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-Name Accounting Standards Codification
-Section 55
-Paragraph 231
-Publisher FASB
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- Definition

The sum of the amounts of estimated penalties and interest recognized in the period arising from income tax examinations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 15
-Subparagraph (c)
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- Definition

Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
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- Definition

The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

+ References

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- Definition

Amount of increase (decrease) in the valuation allowance for a specified deferred tax asset.

+ References

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-Name Accounting Standards Codification
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