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Goodwill and Intangible Assets - Schedule of Goodwill (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 01, 2025	Jul. 31, 2025	Dec. 31, 2023
Goodwill [Roll Forward]
Goodwill, beginning balance	$ 1,872.4	$ 1,426.2			$ 1,447.6
Measurement period adjustment		1.3
Translation adjustment	46.8	(22.0)
Other		(0.7)
Goodwill, ending balance	1,872.4	1,426.2
Certrec
Goodwill [Roll Forward]
Goodwill acquired	55.7
Paragon
Goodwill [Roll Forward]
Goodwill acquired	343.7
Medical
Goodwill [Roll Forward]
Goodwill, beginning balance	634.0	634.0			633.4
Measurement period adjustment		1.3
Translation adjustment	0.0	0.0
Other		(0.7)
Goodwill, ending balance	634.0	634.0
Medical \| Certrec
Goodwill [Roll Forward]
Goodwill acquired	0.0
Medical \| Paragon
Goodwill [Roll Forward]
Goodwill acquired	0.0
Nuclear & Safety
Goodwill [Roll Forward]
Goodwill, beginning balance	1,238.4	792.2			$ 814.2
Measurement period adjustment		0.0
Translation adjustment	46.8	(22.0)
Other		0.0
Goodwill, ending balance	1,238.4	$ 792.2
Nuclear & Safety \| Certrec
Goodwill [Roll Forward]
Goodwill, beginning balance				$ 55.7
Goodwill acquired	55.7
Nuclear & Safety \| Paragon
Goodwill [Roll Forward]
Goodwill, beginning balance			$ 343.7
Goodwill acquired	$ 343.7