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Goodwill and Intangible Assets - Summary of Changes in the Carrying Value of Goodwill (Detail) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Jun. 30, 2021 | Jun. 30, 2020
Goodwill [Line Items] |  |
Beginning Balance | $ 522.6 | $ 511.6
Translation adjustment | 16.0 | (6.1)
Ending balance | 681.5 | 522.6
Capintec |  |
Goodwill [Line Items] |  |
Acquisition |  | 6.0
Premium Analyse |  |
Goodwill [Line Items] |  |
Acquisition |  | 4.3
Selmic |  |
Goodwill [Line Items] |  |
Acquisition |  | 2.7
AWST |  |
Goodwill [Line Items] |  |
Acquisition |  | 4.1
SunNuclear |  |
Goodwill [Line Items] |  |
Acquisition | 130.2 |
Biodex |  |
Goodwill [Line Items] |  |
Acquisition | 11.1 |
Dosimetrics |  |
Goodwill [Line Items] |  |
Acquisition | 1.6 |
Medical |  |
Goodwill [Line Items] |  |
Beginning Balance | 106.8 | 96.7
Translation adjustment | (0.2) | 0.0
Ending balance | 249.5 | 106.8
Medical | Capintec |  |
Goodwill [Line Items] |  |
Acquisition |  | 6.0
Medical | Premium Analyse |  |
Goodwill [Line Items] |  |
Acquisition |  | 0.0
Medical | Selmic |  |
Goodwill [Line Items] |  |
Acquisition |  | 0.0
Medical | AWST |  |
Goodwill [Line Items] |  |
Acquisition |  | 4.1
Medical | SunNuclear |  |
Goodwill [Line Items] |  |
Acquisition | 130.2 |
Medical | Biodex |  |
Goodwill [Line Items] |  |
Acquisition | 11.1 |
Medical | Dosimetrics |  |
Goodwill [Line Items] |  |
Acquisition | 1.6 |
Industrial |  |
Goodwill [Line Items] |  |
Beginning Balance | 415.8 | 414.9
Translation adjustment | 16.2 | (6.1)
Ending balance | 432.0 | 415.8
Industrial | Capintec |  |
Goodwill [Line Items] |  |
Acquisition |  | 0.0
Industrial | Premium Analyse |  |
Goodwill [Line Items] |  |
Beginning Balance | 4.3 |
Acquisition |  | 4.3
Ending balance |  | 4.3
Industrial | Selmic |  |
Goodwill [Line Items] |  |
Beginning Balance | 2.7 |
Acquisition |  | 2.7
Ending balance |  | 2.7
Industrial | AWST |  |
Goodwill [Line Items] |  |
Acquisition |  | $ 0.0
Industrial | SunNuclear |  |
Goodwill [Line Items] |  |
Acquisition | 0.0 |
Industrial | Biodex |  |
Goodwill [Line Items] |  |
Acquisition | 0.0 |
Industrial | Dosimetrics |  |
Goodwill [Line Items] |  |
Acquisition | $ 0.0 |

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