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Acquisitions - Preliminary Intangible Assets Acquired (Details) - USD ($) $ in Thousands |  | 12 Months Ended
--- | --- | ---
Jul. 30, 2018 | Dec. 31, 2020 | Dec. 31, 2019 | Dec. 31, 2018
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquisitions (Note 2) |  | $ 8,180 | $ 0 | $ 139,257
Sotera Health LLC's Nordion Medical Isotope Business | Technical support agreement |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquisitions (Note 2) | $ 67,500 |  |  |
Acquired finite-lived intangible assets, weighted average useful life | 23 years |  |  |
Sotera Health LLC's Nordion Medical Isotope Business | Unpatented technology |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquisitions (Note 2) | $ 33,000 |  |  |
Acquired finite-lived intangible assets, weighted average useful life | 23 years |  |  |
Sotera Health LLC's Nordion Medical Isotope Business | Favorable operating lease |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquisitions (Note 2) | $ 28,157 |  |  |
Sotera Health LLC's Nordion Medical Isotope Business | Customer relationships |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquisitions (Note 2) | $ 10,600 |  |  |
Acquired finite-lived intangible assets, weighted average useful life | 23 years |  |  |
Minimum | Sotera Health LLC's Nordion Medical Isotope Business | Unpatented technology |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquired finite-lived intangible assets, weighted average useful life | 13 years |  |  |
Maximum | Sotera Health LLC's Nordion Medical Isotope Business | Unpatented technology |  |  |  |
Acquired Finite-Lived Intangible Assets [Line Items] |  |  |  |
Acquired finite-lived intangible assets, weighted average useful life | 30 years |  |  |

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- Definition Weighted average amortization period of finite-lived intangible assets acquired either individually or as part of a group of assets, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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- Definition Amount of increase in assets, excluding financial assets, lacking physical substance with a definite life, from an acquisition. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 350 -SubTopic 30 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=66006027&loc=d3e16265-109275 + Details
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