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Income Taxes - Summary of Valuation Allowance (Details) - USD ($) $ in Millions | 2 Months Ended | 4 Months Ended | 12 Months Ended |
--- | --- | --- | --- | ---
Dec. 31, 2021 | Oct. 19, 2021 | Jun. 30, 2021 | Jun. 30, 2020 | Jun. 30, 2019
Income Tax Examination [Line Items] |  |  |  |  |
Valuation allowance | $ 20.7 | $ 30.7 | $ 29.1 | $ 29.0 | $ 18.7
Increases/(decreases) resulting from the Mirion Business Combination | 19.7 | 0.0 | 0.0 | 0.0 |
Increases resulting from other business combinations | 0.0 | 0.0 | 0.5 | 0.3 |
Other increases | 0.0 | 1.6 | 8.6 | 10.0 |
Other decreases | $ 0.0 | 0.0 | $ (9.0) | $ 0.0 |
GSAH |  |  |  |  |
Income Tax Examination [Line Items] |  |  |  |  |
Valuation allowance |  | $ 1.0 |  |  |

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- Definition Valuation Allowance Deferred Tax Asset Increase (Decrease) From Mirion Business Combination + References No definition available. + Details
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- Definition Valuation allowance deferred tax asset increases from business combination. + References No definition available. + Details
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- Definition Amount of deferred tax assets for which it is more likely than not that a tax benefit will not be realized. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (c) -URI http://asc.fasb.org/extlink&oid=121826272&loc=d3e32537-109319 + Details
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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 No definition available. + Details
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- Details
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