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Goodwill and Intangible Assets - Narrative (Details) $ in Millions |  |  |  | 2 Months Ended | 3 Months Ended | 4 Months Ended | 12 Months Ended
--- | --- | --- | --- | --- | --- | --- | ---
Oct. 01, 2023 d | Oct. 01, 2022 reporting_unit | Sep. 30, 2022 reporting_unit | Dec. 31, 2021 USD ($) | Jun. 30, 2022 USD ($) customer | Oct. 19, 2021 USD ($) | Dec. 31, 2023 USD ($) | Dec. 31, 2022 USD ($) reporting_unit | Jun. 30, 2021 USD ($)
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Number of reporting units | 5 | 5 | 6 |  |  |  |  | 6 |
Reporting unit, percentage of terminal future cash flows growth rate |  | 3.50% |  |  |  |  |  |  |
Reporting unit, percentage of fair value in excess of carrying amount | 20.00% | 10.00% |  |  |  |  |  |  |
Goodwill |  |  |  | $ 1,662.6 |  |  | $ 1,447.6 | $ 1,418.0 |
Goodwill impairment |  |  |  | $ 0.0 | $ 55.2 | $ 0.0 | $ 0.0 | $ 211.8 | $ 0.0
Number of reporting units pre-reorganization with excess fair value | reporting_unit |  |  |  |  |  |  |  | 4 |
Number of reporting units pre-reorganization with less fair value | reporting_unit |  |  |  |  |  |  |  | 2 |
Technologies |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Goodwill impairment |  |  |  |  |  |  |  | $ 69.3 |
Medical |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Goodwill impairment |  |  |  |  |  |  |  | $ 87.3 |
Maximum |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Reporting unit, percentage of discount rate | 14.00% | 13.00% |  |  |  |  |  |  |
Minimum |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Reporting unit, percentage of discount rate | 12.00% | 11.00% |  |  |  |  |  |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Revenue from remaining performance obligation (as a percent) |  |  |  |  |  |  | 46.00% |  |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |  |  |  | 1 year |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2025-01-01 |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Revenue from remaining performance obligation (as a percent) |  |  |  |  |  |  | 18.00% |  |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |  |  |  | 1 year |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2026-01-01 |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Revenue from remaining performance obligation (as a percent) |  |  |  |  |  |  | 11.00% |  |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |  |  |  | 1 year |  |
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2027-01-01 |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Revenue from remaining performance obligation (as a percent) |  |  |  |  |  |  | 8.00% |  |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |  |  |  | 1 year |  |
Radiation Monitoring Systems |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Reporting unit, percentage of terminal future cash flows growth rate | 3.50% |  |  |  | 3.50% |  |  |  |
Goodwill |  |  |  |  | $ 257.2 |  |  |  |
Number of customer termination of contract | customer |  |  |  |  | 1 |  |  |  |
Revenue, remaining performance obligation, amount |  |  |  |  | $ 67.0 |  |  |  |
Radiation Monitoring Systems | Maximum |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Reporting unit, percentage of discount rate |  |  |  |  | 10.50% |  |  |  |
Radiation Monitoring Systems | Minimum |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Reporting unit, percentage of discount rate |  |  |  |  | 9.00% |  |  |  |
Radiation Monitoring Systems | Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2024-01-01 |  |  |  |  |  |  |  |  |
Goodwill [Line Items] |  |  |  |  |  |  |  |  |
Revenue from remaining performance obligation (as a percent) |  |  |  |  | 80.00% |  |  |  |
Revenue, remaining performance obligation, expected timing of satisfaction, period |  |  |  |  | 5 years |  |  |  |

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