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Acquisitions - Additional Information (Details) $ in Thousands, $ in Millions				12 Months Ended
	Jan. 02, 2020 USD ($) employee	Jan. 02, 2020 CAD ($) employee	Jul. 30, 2018 USD ($) employee facilities	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 CAD ($)	Dec. 31, 2019 USD ($)
Business Acquisition [Line Items]
Goodwill				$ 274,082		$ 283,708		$ 275,502
Operating lease, right-of-use asset						41,300
Present value of lease liabilities						8,766
Sotera Health LLC's Nordion Medical Isotope Business
Business Acquisition [Line Items]
Business combination, consideration transferred			$ 213,000
Property, plant and equipment			12,948
Intangible assets			139,257
Goodwill			$ 62,495
Number of personnel acquired | employee			150
Number of operating facilities | facilities			2
Increase in Amortization Expense | Sotera Health LLC's Nordion Medical Isotope Business
Business Acquisition [Line Items]
Purchase price allocation adjustment, intangible assets				3,500	$ 6,000
Additional Interest Expense Associated with Incremental Borrowings | Sotera Health LLC's Nordion Medical Isotope Business
Business Acquisition [Line Items]
Purchase price allocation adjustment, interest expense				2,400	$ 5,200
Elimination of Recognized Acquisition Related Costs | Sotera Health LLC's Nordion Medical Isotope Business
Business Acquisition [Line Items]
Elimination of acquisition related costs				2,500
Nuclear Services Group
Business Acquisition [Line Items]
Goodwill				$ 45,000		$ 45,000		$ 45,000
Nuclear Services Group | Laker Energy Products, Ltd
Business Acquisition [Line Items]
Business combination, consideration transferred	$ 17,800	$ 23.3
Business combination, contingent consideration							$ 5.0
Contingent consideration recognized in purchase price							$ 2.5
Property, plant and equipment	8,400
Intangible assets	8,200
Goodwill	5,800
Operating lease, right-of-use asset	2,700
Present value of lease liabilities	$ 2,700
Number of personnel acquired | employee	140	140

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