Sotera Health (SHC) 10-Q 5 May 22 2022 Q1 Quarterly report Financial data

Cover

Cover - shares	3 Months Ended
	Mar. 31, 2022	Apr. 28, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Mar. 31, 2022
Document Transition Report	false
Entity File Number	001-39729
Entity Registrant Name	SOTERA HEALTH COMPANY
Entity Incorporation, State or Country Code	DE
Entity Tax Identification Number	47-3531161
Entity Address, Address Line One	9100 South Hills Blvd
Entity Address, Address Line Two	Suite 300
Entity Address, City or Town	Broadview Heights
Entity Address, State or Province	OH
Entity Address, Postal Zip Code	44147
City Area Code	440
Local Phone Number	262-1410
Title of 12(b) Security	Common Stock, $0.01 par value per share
Trading Symbol	SHC
Security Exchange Name	NASDAQ
Entity Current Reporting Status	Yes
Entity Interactive Data Current	Yes
Entity Filer Category	Large Accelerated Filer
Entity Small Business	false
Entity Emerging Growth Company	false
Entity Shell Company	false
Entity Common Stock, Shares Outstanding		282,817,234
Entity Central Index Key	0001822479
Current Fiscal Year End Date	--12-31
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q1
Amendment Flag	false

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 121,440	$ 106,917
Restricted cash short-term	6	7
Accounts receivable, net of allowance for uncollectible accounts of $1,458 and $1,287, respectively	114,763	108,183
Inventories, net	45,701	54,288
Prepaid expenses and other current assets	83,956	71,923
Income taxes receivable	5,694	4,643
Total current assets	371,560	345,961
Property, plant, and equipment, net	669,161	650,797
Operating lease assets	36,984	39,946
Deferred income taxes	5,769	5,885
Investment in unconsolidated affiliate	9,550	9,405
Post-retirement asset	7,285	5,478
Other assets	27,488	12,866
Other intangible assets, net	582,144	598,844
Goodwill	1,125,828	1,120,320
Total assets	2,835,769	2,789,502
Current liabilities:
Accounts payable	55,221	72,868
Accrued liabilities	60,459	61,861
Deferred revenue	12,928	8,669
Current portion of finance lease obligations	1,342	1,160
Current portion of operating lease obligations	8,906	9,289
Current portion of asset retirement obligations	627	619
Income taxes payable	4,368	6,695
Total current liabilities	143,851	161,161
Total long-term debt, less debt issuance costs and debt discounts	1,744,541	1,743,534
Finance lease obligations, less current portion	40,014	40,877
Operating lease obligations, less current portion	31,065	33,017
Noncurrent asset retirement obligations	42,995	41,833
Deferred lease income	20,916	20,745
Post-retirement obligations	11,608	11,464
Noncurrent liabilities	16,188	16,274
Deferred income taxes	142,461	134,501
Total liabilities	2,193,639	2,203,406
See Commitments and contingencies note
Equity:
Common stock, with $0.01 par value, 1,200,000 shares authorized; 286,037 shares issued at March 31, 2022 and December 31, 2021, respectively	2,860	2,860
Preferred stock, with $0.01 par value, 120,000 authorized; no shares issued at March 31, 2022 and December 31, 2021, respectively	0	0
Treasury stock, at cost (3,107 and 3,052 shares at March 31, 2022 and December 31, 2021, respectively)	(33,536)	(33,545)
Additional paid-in capital	1,177,097	1,172,593
Retained deficit	(441,605)	(472,246)
Accumulated other comprehensive loss	(62,686)	(83,566)
Total equity attributable to Sotera Health Company	642,130	586,096
Noncontrolling interests	0	0
Total equity	642,130	586,096
Total liabilities and equity	$ 2,835,769	$ 2,789,502

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Allowance for uncollectible accounts	$ 1,458	$ 1,287
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (in shares)	1,200,000,000	1,200,000,000
Common stock, shares issued (in shares)	286,037,000	286,037,000
Preferred stock, par value (in dollars per share)	$ 0.01	$ 0.01
Preferred stock, shares authorized (in shares)	120,000,000	120,000,000
Preferred stock, shares issued (in shares)	0	0
Treasury stock (in shares)	3,107,000	3,052,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Revenues:
Total net revenues	$ 236,754	$ 212,148
Cost of revenues:
Total cost of revenues	107,879	96,776
Gross profit	128,875	115,372
Operating expenses:
Selling, general and administrative expenses	59,542	52,465
Amortization of intangible assets	15,841	16,543
Total operating expenses	75,383	69,008
Operating income	53,492	46,364
Interest expense, net	10,404	21,282
Loss on extinguishment of debt	0	14,312
Foreign exchange loss	788	578
Other income, net	(2,967)	(3,890)
Income before income taxes	45,267	14,082
Provision for income taxes	14,626	3,017
Net income	30,641	11,065
Less: Net income attributable to noncontrolling interests	0	223
Net income attributable to Sotera Health Company	30,641	10,842
Other comprehensive income (loss) net of tax:
Pension and post-retirement benefits (net of taxes of $(92) and $(84), respectively)	(274)	(249)
Interest rate derivatives (net of taxes of $2,109 and $0, respectively)	6,179	0
Foreign currency translation	14,975	(3,086)
Comprehensive income	51,521	7,730
Less: comprehensive income attributable to noncontrolling interests	0	208
Comprehensive income attributable to Sotera Health Company	$ 51,521	$ 7,522
Earnings per share:
Basic (in dollars per share)	$ 0.11	$ 0.04
Diluted (in dollars per share)	$ 0.11	$ 0.04
Weighted average number of shares outstanding:
Basic (in shares)	279,829	278,827
Diluted (in shares)	279,908	278,968
Service
Revenues:
Total net revenues	$ 206,218	$ 188,698
Cost of revenues:
Total cost of revenues	94,576	85,036
Product
Revenues:
Total net revenues	30,536	23,450
Cost of revenues:
Total cost of revenues	$ 13,303	$ 11,740

Consolidated Statements of Op_2

Consolidated Statements of Operations and Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Statement [Abstract]
Pension and post-retirement benefits, tax	$ (92)	$ (84)
Interest rate swaps, tax	$ 2,109	$ 0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Operating activities:
Net income	$ 30,641	$ 11,065
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	15,867	15,379
Amortization of intangible assets	20,182	22,282
Loss on extinguishment of debt	0	14,312
Deferred income taxes	5,633	(3,637)
Share-based compensation expense	4,538	3,449
Accretion of asset retirement obligations	520	551
Unrealized foreign exchange losses	2,430	2,354
Unrealized gain on derivatives not designated as hedging instruments	(7,364)	(853)
Amortization of debt issuance costs	1,414	1,663
Other	(1,989)	(2,843)
Changes in operating assets and liabilities:
Accounts receivable	(6,387)	(4,134)
Inventories	9,323	1,099
Other current assets	(8,934)	(2,324)
Accounts payable	(12,742)	6,625
Accrued liabilities	2,479	(5,542)
Income taxes payable / receivable	(5,222)	(4,518)
Other liabilities	(81)	1,513
Other long-term assets	(341)	(282)
Net cash provided by operating activities	49,967	56,159
Investing activities:
Purchases of property, plant and equipment	(35,546)	(20,942)
Purchase of mandatorily redeemable noncontrolling interest in Nelson Laboratories Fairfield, Inc.	0	(12,425)
Purchase of BioScience Laboratories, LLC, net of cash acquired	0	(13,152)
Adjustment to purchase of Regulatory Compliance Associates Inc.	63	0
Net cash used in investing activities	(35,483)	(46,519)
Financing activities:
Payments of debt issuance costs	(31)	(3,435)
Other financing activities	(418)	(348)
Net cash used in financing activities	(449)	(3,783)
Effect of exchange rate changes on cash and cash equivalents	487	(295)
Net increase in cash and cash equivalents, including restricted cash	14,522	5,562
Cash and cash equivalents, including restricted cash, at beginning of period	106,924	102,454
Cash and cash equivalents, including restricted cash, at end of period	121,446	108,016
Supplemental disclosures of cash flow information:
Cash paid during the period for interest	15,809	19,745
Cash paid during the period for income taxes, net of tax refunds received	13,505	11,561
Equipment purchases included in accounts payable	$ 9,508	$ 7,389

Consolidated Statements of Equi

Consolidated Statements of Equity - USD ($) shares in Thousands, $ in Thousands	Total	Common Stock	Treasury Stock	Additional Paid-In Capital	Retained Earnings / (Accumulated Deficit)	Accumulated Other Comprehensive (Loss) Income	Noncontrolling Interests
Balance (in shares) at Dec. 31, 2020		283,248
Balance at Dec. 31, 2020	$ 454,574	$ 2,860	$ (34,000)	$ 1,166,412	$ (589,128)	$ (93,842)	$ 2,272
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation plans (in shares)		$ (348)
Share-based compensation plans	3,440			3,440
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	(249)					(249)
Foreign currency translation	(3,086)					(3,071)	(15)
Interest rate derivatives, net of tax	0
Net income	11,065				10,842		223
Balance (in shares) at Mar. 31, 2021		282,900
Balance at Mar. 31, 2021	465,744	$ 2,860	(34,000)	1,169,852	(578,286)	(97,162)	2,480
Balance (in shares) at Dec. 31, 2021		282,985
Balance at Dec. 31, 2021	586,096	$ 2,860	(33,545)	1,172,593	(472,246)	(83,566)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation plans (in shares)		$ (55)
Share-based compensation plans	4,513		9	4,504
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	(274)					(274)
Foreign currency translation	14,975					14,975
Interest rate derivatives, net of tax	6,179					6,179
Net income	30,641				30,641
Balance (in shares) at Mar. 31, 2022		282,930
Balance at Mar. 31, 2022	$ 642,130	$ 2,860	$ (33,536)	$ 1,177,097	$ (441,605)	$ (62,686)	$ 0

Basis of Presentation

Basis of Presentation	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Basis of Presentation	Basis of Presentation Principles of Consolidation – Sotera Health Company (also referred to herein as the “Company,” “we,” “our,” “us” or “its”), is a global provider of mission-critical sterilization and lab testing and advisory services to the medical device and pharmaceutical industries with operations primarily in the Americas, Europe and Asia. We operate and report in three segments, Sterigenics, Nordion and Nelson Labs. We describe our reportable segments in Note 18, “Segment Information”. All significant intercompany balances and transactions have been eliminated in consolidation. Noncontrolling interests represented the noncontrolling stockholders’ proportionate share of the total equity in the Company’s consolidated subsidiaries. In the second quarter of 2021, we purchased the outstanding noncontrolling interests of 15% and 33% in our two China subsidiaries. Refer to Note 4, “Acquisitions” for additional details. Prior to our acquisition of the noncontrolling interests in our two subsidiaries in China, we consolidated the results of operations of these subsidiaries with our results of operations and reflected the noncontrolling interests on our Consolidated Statements of Operations and Comprehensive Income as “Net income attributable to noncontrolling interests.” On March 11, 2021, we purchased the 15% noncontrolling interest that remained from the August 2018 acquisition of Nelson Laboratories Fairfield, Inc. (“Nelson Labs Fairfield”). As the purchase of this noncontrolling interest was mandatorily redeemable, no earnings were allocated to this noncontrolling interest. See Note 4, “Acquisitions” for additional details. In July 2020, we acquired a 60% equity ownership interest in a joint venture to construct an E-beam facility in Alberta, Canada in connection with our acquisition of Iotron Industries Canada, Inc. (“Iotron”). We have determined this to be an investment in a variable interest entity (“VIE”). The investment is not consolidated as the Company has concluded that we are not the primary beneficiary of the VIE. The Company accounts for the joint venture using the equity method. The investment is reflected within “Investment in unconsolidated affiliates” on the Consolidated Balance Sheets. Use of Estimates – In preparing our consolidated financial statements in conformity with U.S. Generally Accepted Accounting Principles (“GAAP”), we make estimates and assumptions that affect the amounts reported and the accompanying notes. We regularly evaluate the estimates and assumptions used and revise them as new information becomes available. Actual results may vary from those estimates. Interim Financial Statements – The accompanying consolidated financial statements include the assets, liabilities, operating results, and cash flows of the Company and its wholly owned subsidiaries. These financial statements are prepared in accordance with U.S. GAAP for interim financial information and the instructions to the Quarterly Report on Form 10-Q and Rule 10-01 of Regulation S-X. Accordingly, they do not include all of the information and footnotes required by U.S. GAAP for complete financial statements. In the opinion of management, all adjustments (consisting of normal recurring adjustments) considered necessary for a fair presentation have been included. These unaudited interim financial statements should be read in conjunction with the Company's annual consolidated financial statements and accompanying notes on Form 10-K for the year ended December 31, 2021.

Recent Accounting Standards

Recent Accounting Standards	3 Months Ended
	Mar. 31, 2022
Accounting Changes and Error Corrections [Abstract]
Recent Accounting Standards	Recent Accounting Standards Adoption of Accounting Standard Updates Effective January 1, 2022, we adopted Accounting Standards Update (“ASU”) 2016-13, Financial Instruments – Credit Losses (“ASU 2016-13”): Measurement of Credit Losses on Financial Instruments, and the subsequently issued additional guidance that modified ASU 2016-13 which was originally issued by the Financial Accounting Standards Board (“FASB”) in June 2016. The standard requires an entity to change its accounting approach in determining impairment of certain financial instruments, including trade receivables, from an “incurred loss” to a “current expected credit loss” model. The adoption of this standard did not have a material impact on our consolidated financial statements and disclosures. Effective January 1, 2022, we adopted ASU 2019-12 - Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes which was issued by the FASB in December 2019. The standard simplifies the accounting for income taxes and makes a number of changes meant to add or clarify guidance on accounting for income taxes. The adoption of this standard did not have a material impact on our consolidated financial statements and disclosures. ASU’s Issued But Not Yet Adopted In October 2021, the FASB issued ASU 2021-08 - Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers (“ASU 2021-08”). The amendments in ASU 2021-08 require that an acquiring entity recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contract with Customers (“ASC Topic 606”). At the acquisition date, an acquirer should account for the related revenue contracts in accordance with ASC Topic 606 as if it had originated the contracts. For public business entities, these amendments are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We are currently assessing the effect that ASU 2021-08 will have on our financial position, results of operations, and disclosures.

Revenue Recognition

Revenue Recognition	3 Months Ended
	Mar. 31, 2022
Revenue from Contract with Customer [Abstract]
Revenue Recognition	Revenue Recognition The following table shows disaggregated net revenues from contracts with external customers by timing of revenue and by segment for the three months ended March 31, 2022 and 2021: (thousands of U.S. dollars) Three Months Ended March 31, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 149,462 $ 33,285 $ — $ 182,747 Over time — 717 53,290 54,007 Total $ 149,462 $ 34,002 $ 53,290 $ 236,754 (thousands of U.S. dollars) Three Months Ended March 31, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 131,151 $ 25,918 $ — $ 157,069 Over time — — 55,079 55,079 Total $ 131,151 $ 25,918 $ 55,079 $ 212,148 Contract Balances As of March 31, 2022, and December 31, 2021, contract assets included in prepaid expenses and other current assets on the Consolidated Balance Sheets totaled approximately $18.5 million and $15.6 million, respectively, resulting from revenue recognized over time in excess of the amount billed to the customer. When we receive consideration from a customer prior to transferring goods or services under the terms of a sales contract, we record deferred revenue, which represents a contract liability. Deferred revenue totaled $12.9 million and $8.7 million at March 31, 2022 and December 31, 2021, respectively. We recognize deferred revenue after all revenue recognition criteria are met.

Acquisitions

Acquisitions	3 Months Ended
	Mar. 31, 2022
Business Combination and Asset Acquisition [Abstract]
Acquisitions	Acquisitions Acquisition of Regulatory Compliance Associates Inc. On November 4, 2021, we acquired Regulatory Compliance Associates Inc. (“RCA”) for approximately $31.0 million, net of $0.6 million of cash acquired. RCA is an industry leader in providing life sciences consulting focused on quality, regulatory, and technical advisory services for the pharmaceutical, medical device and combination device industries. Headquartered in Pleasant Prairie, Wisconsin, RCA will expand and further strengthen the technical consulting and expert advisory capabilities of our Nelson Labs segment. The purchase price of RCA was allocated to the underlying assets acquired and liabilities assumed based upon management's estimated fair values at the date of acquisition. Changes to the allocation of the purchase price may occur as these measurements are completed. As of March 31, 2022, approximately $20.7 million of goodwill was recorded related to the RCA acquisition, representing the excess of the purchase price over preliminary estimated fair values of all the assets acquired and liabilities assumed. Based on our preliminary estimates, we also recorded $12.5 million of finite-lived intangible assets, primarily related to customer relationships. The purchase price allocation will be finalized within a measurement period not to exceed one year from closing. We funded this acquisition using available cash. The acquisition price and the results of operations for this acquired entity are not material in relation to our consolidated financial statements. Acquisition of Noncontrolling Interests in China Subsidiaries On May 18, 2021, we acquired the remaining 15% and 33% noncontrolling interests associated with our two subsidiaries located in China. As a result, both entities are now 100% owned by the Company. The purchase price of the remaining equity interests was approximately $8.6 million, net of the cancellation of an $0.8 million demand note. We paid 90% of the cash consideration on the acquisition date. The remaining amounts were partially settled in post-closing payments in the third quarter of 2021; $0.2 million of the post-closing payment remains outstanding as of March 31, 2022 subject to the terms of the equity transfer agreements. As a result of the transactions, we continue to consolidate both of these subsidiaries, however, as of May 18, 2021, we no longer record noncontrolling interests in the consolidated financial statements as these subsidiaries are fully owned by the Company. The purchases were accounted for as equity transactions. As a result of these transactions, noncontrolling interests were reduced by $2.8 million reflecting the carrying value of the interest with $5.8 million of the difference charged to additional paid-in capital. Acquisition of Mandatorily Redeemable Noncontrolling Interest - Nelson Labs Fairfield On March 11, 2021, we completed the acquisition of the remaining 15% ownership of Nelson Labs Fairfield for $12.4 million, resulting in a gain of $1.2 million included in “Other expense (income), net” in the Consolidated Statements of Operations and Comprehensive Income relative to the $13.6 million previously accrued. Pursuant to the terms of this acquisition, we initially acquired 85% of the equity interests of Nelson Labs Fairfield in August 2018 and were obligated to acquire the remaining 15% noncontrolling interest within three years from the date of the acquisition. Acquisition of BioScience Laboratories, LLC On March 8, 2021, we acquired BioScience Laboratories, LLC (“BioScience Labs”) for approximately $13.5 million, net of $0.2 million of cash acquired plus the contemporaneous repayment of BioScience Labs’ outstanding debt of $1.9 million. BioScience Labs is a provider of outsourced topical antimicrobial product testing in the pharmaceutical, medical device, and consumer products industries with one location in Bozeman, Montana. BioScience Labs is included within the Nelson Labs segment. The purchase price of BioScience Labs was allocated to the underlying assets acquired and liabilities assumed based upon management's estimated fair values at the date of acquisition. Changes to the allocation of the purchase price may occur as these measurements are completed. Approximately $8.4 million of goodwill was recorded related to the BioScience Labs acquisition, representing the excess of the purchase price over preliminary estimated fair values of all the assets acquired and liabilities assumed. We funded this acquisition using available cash. The acquisition price and the results of operations for this acquired entity are not material in relation to our consolidated financial statements.

Inventories

Inventories	3 Months Ended
	Mar. 31, 2022
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Raw materials and supplies $ 32,451 $ 41,514 Work-in-process 758 3,919 Finished goods 12,618 8,979 45,827 54,412 Reserve for excess and obsolete inventory (126) (124) Inventories, net $ 45,701 $ 54,288

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	3 Months Ended
	Mar. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid Expenses and Other Current Assets	Prepaid Expenses and Other Current Assets Prepaid expenses and other current assets consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Prepaid taxes $ 26,752 $ 24,937 Prepaid business insurance 8,107 10,707 Prepaid rent 1,203 920 Customer contract assets 18,547 15,565 Insurance and indemnification receivables 3,805 3,144 Current deposits 493 623 Prepaid maintenance contracts 336 279 Value added tax receivable 1,500 2,512 Prepaid software licensing 1,428 2,055 Stock supplies 3,587 3,374 Embedded derivative assets 1,842 496 Other 16,356 7,311 Prepaid expenses and other current assets $ 83,956 $ 71,923

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	3 Months Ended
	Mar. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Changes to goodwill during the three months ended March 31, 2022 were as follows: (thousands of U.S. dollars) Sterigenics Nordion Nelson Labs Total Goodwill at December 31, 2021 $ 660,743 $ 288,905 $ 170,672 $ 1,120,320 RCA acquisition measurement period adjustments — — 56 56 Changes due to foreign currency exchange rates 1,733 4,423 (704) 5,452 Goodwill at March 31, 2022 $ 662,476 $ 293,328 $ 170,024 $ 1,125,828 Other intangible assets consisted of the following: (thousands of U.S. dollars) Gross Carrying Amount Accumulated Amortization As of March 31, 2022 Finite-lived intangible assets Customer relationships $ 668,034 $ 380,341 Proprietary technology 89,037 46,268 Trade names 170 139 Land-use rights 9,773 1,650 Sealed source and supply agreements 245,334 114,818 Other 6,483 2,628 Total finite-lived intangible assets 1,018,831 545,844 Indefinite-lived intangible assets Regulatory licenses and other (a) 83,375 — Trade names / trademarks 25,782 — Total indefinite-lived intangible assets 109,157 — Total $ 1,127,988 $ 545,844 As of December 31, 2021 Gross Carrying Amount Accumulated Amortization Finite-lived intangible assets Customer relationships $ 668,628 $ 365,935 Proprietary technology 88,826 44,866 Trade names 145 116 Land-use rights 9,744 1,586 Sealed source and supply agreements 241,611 109,838 Other 6,454 2,166 Total finite-lived intangible assets 1,015,408 524,507 Indefinite-lived intangible assets Regulatory licenses and other (a) 82,110 — Trade names / trademarks 25,833 — Total indefinite-lived intangible assets 107,943 — Total $ 1,123,351 $ 524,507 (a) Includes certain transportation certifications, a class 1B nuclear license and other intangibles related to obtaining such licensure. These assets are considered indefinite-lived as the decision for renewal by the Canadian Nuclear Safety Commission is highly based on a licensee’s previous assessments, reported incidents, and annual compliance and inspection results. New applications for license can take a significant amount of time and cost; whereas an existing licensee with a historical record of compliance and current operating conditions more than likely ensures renewal for another 10 year license period as Nordion has demonstrated over its 75 years of history. Amounts include the impact of foreign currency translation. Amortization expense for other intangible assets was $20.2 million ($4.3 million is included in “Cost of revenues” and $15.9 million in “Selling, general and administrative expenses”) in the Consolidated Statements of Operations and Comprehensive Income and $22.3 million ($5.8 million is included in “Cost of revenues” and $16.5 million in “Selling, general and administrative expenses”) in the Consolidated Statements of Operations and Comprehensive Income for the three months ended March 31, 2022 and 2021, respectively. The estimated aggregate amortization expense for finite-lived intangible assets for each of the next five years and thereafter is as follows: (thousands of U.S. dollars) For the remainder of 2022 $ 62,157 2023 82,016 2024 81,237 2025 43,437 2026 23,181 Thereafter 180,959 Total $ 472,987 The weighted-average remaining useful life of the finite-lived intangible assets was approximately 9.5 years as of March 31, 2022.

Accrued Liabilities

Accrued Liabilities	3 Months Ended
	Mar. 31, 2022
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Accrued employee compensation $ 29,391 $ 33,334 Legal reserves 3,134 3,259 Accrued interest expense 10,132 10,755 Embedded derivatives 308 — Professional fees 7,708 4,314 Accrued utilities 1,833 1,797 Insurance accrual 1,407 2,068 Accrued taxes 2,333 2,209 Other 4,213 4,125 Accrued liabilities $ 60,459 $ 61,861

Long-Term Debt

Long-Term Debt	3 Months Ended
	Mar. 31, 2022
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Term loan, due 2026 $ 1,763,100 $ 1,763,100 Other long-term debt 450 450 Total long-term debt 1,763,550 1,763,550 Less unamortized debt issuance costs and debt discounts (19,009) (20,016) Total long-term debt, less debt issuance costs and debt discounts $ 1,744,541 $ 1,743,534 Debt Facilities Senior Secured Credit Facilities On December 13, 2019, Sotera Health Holdings, LLC (“SHH”), our wholly owned subsidiary, entered into senior secured first lien credit facilities (the “Senior Secured Credit Facilities”), consisting of both a prepayable senior secured first lien term loan (the “Term Loan”) and a senior secured first lien revolving credit facility (the “Revolving Credit Facility”) pursuant to a first lien credit agreement (the “Credit Agreement”). The Revolving Credit Facility and Term Loan mature on June 13, 2026 and December 13, 2026, respectively. The total borrowing capacity under the Revolving Credit Facility is $347.5 million. The Senior Secured Credit Facilities also provide SHH the right at any time and under certain conditions to request incremental term loans or incremental revolving credit commitments based on a formula defined in the Senior Secured Credit Facilities. As of March 31, 2022 and December 31, 2021, total borrowings under the Term Loan were $1,763.1 million, and there were no borrowings outstanding on the Revolving Credit Facility. The weighted average interest rate on borrowings under the Term Loan for the three months ended March 31, 2022 and March 31, 2021 was 3.25% and 3.73%, respectively. On January 20, 2021, we closed on an amendment repricing our Term Loan. The interest rate spread over the London Interbank Offered Rate (“LIBOR”) on the facility was reduced from 450 basis points to 275 basis points, and the facility’s LIBOR floor was reduced from 100 basis points to 50 basis points. The changes result in an effective reduction in current interest rates of 225 basis points. In connection with this amendment, we wrote off $11.3 million of unamortized debt issuance and discount costs and incurred an additional $2.9 million of expense related to debt issuance costs attributable to the refinancing. These costs were recorded to “Loss on extinguishment of debt” in our Consolidated Statements of Operations and Comprehensive Income. On March 26, 2021, we amended the Revolving Credit Facility, to (i) decrease the Applicable Rate (as defined in the Credit Agreement) related to any Revolving Loans (as defined in the Credit Agreement) from a rate per annum that ranged from an alternative base rate (“ABR”) plus 2.50% to ABR plus 3.00% depending on SHH’s Senior Secured First Lien Net Leverage Ratio to ABR plus 1.75%; and in the case of Eurodollar Loans (as defined in the Credit Agreement) from a rate per annum which ranged from the Adjusted LIBOR plus 3.50% to the Adjusted LIBOR plus 4.00% depending on SHH’s Senior Secured First Lien Net Leverage Ratio (as defined in the Credit Agreement), to the Adjusted LIBOR (as defined in the Credit Agreement) plus 2.75%, and (ii) extend the maturity date of the Revolving Facility from December 13, 2024 to June 13, 2026. The other material terms of the Credit Agreement are unchanged and the amendment did not change the capacity of our Revolving Credit Facility. No unamortized debt issuance costs associated with the Revolving Credit Facility were written off and direct fees and costs incurred in connection with the amendment were immaterial. As of March 31, 2022 and December 31, 2021, capitalized debt issuance costs totaled $2.5 million and $2.7 million, respectively, and debt discounts totaled $16.5 million and $17.3 million, respectively, related to the Senior Secured Credit Facilities. Such costs are recorded as a reduction of debt on our Consolidated Balance Sheets and amortized as a component of interest expense over the term of the debt agreement. The Senior Secured Credit Facilities contain additional covenants that, among other things, restrict, subject to certain exceptions, our ability and the ability of our restricted subsidiaries to engage in certain activities, such as incur indebtedness or permit to exist any lien on any property or asset now owned or hereafter acquired, as specified in the Senior Secured Credit Facilities. The Senior Secured Credit Facilities also contain certain customary affirmative covenants and events of default, including upon a change of control. As of March 31, 2022, we were in compliance with all the Senior Secured Credit Facilities covenants. All of SHH’s obligations under the Senior Secured Credit Facilities are unconditionally guaranteed by the Company and each existing and subsequently acquired or organized direct or indirect wholly-owned domestic restricted subsidiary of the Company, with customary exceptions including, among other things, where providing such guarantees is not permitted by law, regulation or contract or would result in material adverse tax consequences. All obligations under the Senior Secured Credit Facilities, and the guarantees of such obligations, are secured by substantially all assets of the borrower and guarantors, subject to permitted liens and other exceptions and exclusions, as outlined in the Senior Secured Credit Facilities. Outstanding letters of credit are collateralized by encumbrances against the Revolving Credit Facility and the collateral pledged thereunder, or by cash placed on deposit with the issuing bank. As of March 31, 2022, the Company had $69.2 million of letters of credit issued against the Revolving Credit Facility, resulting in total availability under the Revolving Credit Facility of $278.3 million. Term Loan Interest Rate Risk Management The Company utilizes interest rate derivatives to eliminate the variability of cash flows in the interest payments associated with the Term Loan due to changes in LIBOR (or its successor). For additional information on the derivative instruments described above, refer to Note 17, “Financial Instruments and Financial Risk”, “Derivatives Instruments.” First Lien Notes On July 31, 2020, SHH issued $100.0 million aggregate principal amount of senior secured first lien notes due 2026 (the “First Lien Notes”), which were scheduled to mature on December 13, 2026. On August 27, 2021 SHH redeemed in full the $100.0 million aggregate principal amount of the First Lien Notes. In connection with this redemption, the Company paid a $3.0 million early redemption premium, in accordance with the terms of the First Lien Notes Indenture, and wrote off $3.4 million of debt issuance and discount costs. The Company recognized these expenses within “Loss on extinguishment of debt” in our Consolidated Statements of Operations and Comprehensive Income for the year ended December 31, 2021. Prior to the redemption, the First Lien Notes bore interest at a rate equal to LIBOR subject to a 1.00% floor plus 6.00% per annum. Interest was payable on a quarterly basis with no principal due until maturity. The weighted average interest rate on the First Lien Notes during 2021 up to the August 27, 2021 redemption date was 7.00%. Aggregate Maturities Aggregate maturities of the Company’s long-term debt, excluding debt discounts, as of March 31, 2022, are as follows: (thousands of U.S. dollars) 2022 $ — 2023 450 2024 — 2025 — 2026 1,763,100 Thereafter — Total $ 1,763,550

Income Taxes

Income Taxes	3 Months Ended
	Mar. 31, 2022
Income Tax Disclosure [Abstract]
Income Taxes	Income Taxes Income tax expense is provided on an interim basis based upon our estimate of the annual effective income tax rate. In determining the estimated annual effective income tax rate, we analyze various factors, including projections of our annual earnings and the taxing jurisdictions where the earnings will occur, the impact of state and local taxes, our ability to utilize tax credits and net operating loss carryforwards and available tax planning alternatives. Our effective tax rate was 32.3 % and 21.4% for the three months ended March 31, 2022 and 2021, respectively. Income tax expense for the three months ended March 31, 2022 and March 31, 2021 differs from the statutory rate primarily due to a net increase in the valuation allowance attributable to the limitation on the deductibility of interest expense, the impact of the foreign rate differential, and global intangible low-tax income (“GILTI”). Provision for income tax expense for the three months ended March 31, 2021 was offset by a discrete item, which reversed the valuation allowance on deferred tax assets related to certain asset retirement obligations.

Employee Benefits

Employee Benefits	3 Months Ended
	Mar. 31, 2022
Postemployment Benefits [Abstract]
Employee Benefits	Employee Benefits The Company sponsors various post-employment benefit plans including, in certain countries outside the U.S., defined benefit and defined contribution pension plans, retirement compensation arrangements, and plans that provide extended health care coverage to retired employees, the majority of which relate to Nordion. Defined benefit pension plan The interest cost, expected return on plan assets, and amortization of net actuarial loss are recorded net in “Other income, net” and the service cost component is included in the same financial statement line item as the applicable employee’s wages in the Consolidated Statements of Operations and Comprehensive Income. The components of net periodic pension cost for the defined benefit plans for the three months ended March 31, 2022 and 2021 were as follows: Three Months Ended March 31, (thousands of U.S. dollars) 2022 2021 Service cost $ 249 $ 298 Interest cost 1,903 1,613 Expected return on plan assets (3,704) (3,557) Amortization of net actuarial loss — 267 Net periodic benefit $ (1,552) $ (1,379) Other benefit plans Other benefit plans are all related to our foreign subsidiaries and include a supplemental retirement arrangement, a retirement and termination allowance, and post-retirement benefit plans, which include contributory health and dental care benefits and contributory life insurance coverage. All but one, non-pension post-employment benefit plans are unfunded. The components of net periodic pension cost for the other benefit plans for the three months ended March 31, 2022 and 2021 were as follows: Three Months Ended March 31, (thousands of U.S. dollars) 2022 2021 Service cost $ 4 $ 7 Interest cost 65 59 Amortization of net actuarial (gain) loss (2) 8 Net periodic benefit cost $ 67 $ 74 We currently expect funding requirements of approximately $3.1 million in each of the next five years to fund the regulatory solvency deficit, as defined by Canadian federal regulation, which requires solvency testing on defined benefit pension plans.

Related Parties

Related Parties	3 Months Ended
	Mar. 31, 2022
Related Party Transactions [Abstract]
Related Parties	Related PartiesWe do business with a number of other companies affiliated with Warburg Pincus and GTCR, whom we refer to collectively as our “Sponsors”. All transactions with these companies have been conducted in the ordinary course of our business and are not material to our operations.

Other Comprehensive Income (Los

Other Comprehensive Income (Loss)	3 Months Ended
	Mar. 31, 2022
Equity [Abstract]
Other Comprehensive Income (Loss)	Other Comprehensive Income (Loss) Amounts in accumulated other comprehensive income (loss) are presented net of the related tax. Foreign currency translation is not adjusted for income taxes. Changes in our accumulated other comprehensive income (loss) balances, net of applicable tax, were as follows: (thousands of U.S. dollars) Defined Benefit Plans Foreign Currency Translation Interest Rate Swaps Total Beginning balance – January 1, 2022 $ (17,581) $ (66,389) $ 404 $ (83,566) Other comprehensive income (loss) before reclassifications (272) 14,975 6,179 20,882 Amounts reclassified from accumulated other comprehensive income (loss) (2) (a) — — (b) (2) Net current-period other comprehensive income (loss) (274) 14,975 6,179 20,880 Ending balance – March 31, 2022 $ (17,855) $ (51,414) $ 6,583 $ (62,686) Beginning balance – January 1, 2021 $ (44,143) $ (49,699) $ — $ (93,842) Other comprehensive income (loss) before reclassifications (524) (3,071) — (3,595) Amounts reclassified from accumulated other comprehensive income (loss) 275 (a) — — 275 Net current-period other comprehensive income (loss) (249) (3,071) — (3,320) Ending balance – March 31, 2021 $ (44,392) $ (52,770) $ — $ (97,162) (a) For defined benefit pension plans, amounts reclassified from accumulated other comprehensive income (loss) are recorded to “Other income, net” within the Consolidated Statements of Operations and Comprehensive Income. (b) For interest rate derivatives, amounts reclassified from accumulated other comprehensive income (loss) are recorded to “Interest expense, net” within the Consolidated Statements of Operations and Comprehensive Income.

Share-Based Compensation

Share-Based Compensation	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Share-Based Compensation	Share-Based Compensation Pre-IPO Awards Restricted stock distributed in respect of pre-IPO Class B-1 time vesting units vests on a daily basis pro rata over the five Restricted stock distributed in respect of pre-IPO Class B-2 Units (which were considered performance vesting units) are scheduled to vest only upon satisfaction of certain thresholds. These units generally vest as of the first date on which (i) our Sponsors have received actual cash proceeds in an amount equal to or in excess of at least two and one-half times their invested capital in Sotera Health Topco Parent, L.P. (of which the Company was a direct wholly owned subsidiary prior to the IPO) and (ii) the Sponsors’ internal rate of return exceeds twenty percent, subject to such grantee’s continued services through such date. In the event of a change in control of the Company, any outstanding shares of our common stock distributed in respect of Class B-2 Units that remain unvested immediately following the consummation of such a change in control of the Company shall be immediately canceled and forfeited without compensation. Stock based compensation expense attributed to the pre-IPO Class B-2 awards was recorded in the fourth quarter of 2020 as the related performance conditions were considered probable of achievement and the implied service conditions were met. As of March 31, 2022, these awards remain unvested. We recognized $0.6 million and $0.7 million of share-based compensation expense related to the pre-IPO Class B-1 awards for the three months ended March 31, 2022 and 2021, respectively. A summary of the activity for the three months ended March 31, 2022 related to the restricted stock awards distributed to the Company service providers in respect of the pre-IPO awards (Class B-1 and B-2 Units) is presented below: Restricted Stock - Pre- IPO B-1 Restricted Stock - Pre- IPO B-2 Unvested at December 31, 2021 1,206,089 2,023,959 Forfeited (15,793) (40,616) Vested (144,713) — Unvested at March 31, 2022 1,045,583 1,983,343 2021 Omnibus Incentive Plan We maintain a long-term incentive plan (the “2020 Omnibus Incentive Plan” or the “2020 Plan”) that allows for grants of incentive stock options to employees (including employees of any of our subsidiaries), nonstatutory stock options, restricted stock awards (“RSAs”), restricted stock units (“RSUs”) and other cash-based, equity-based or equity-related awards to employees, directors, and consultants, including employees or consultants of our subsidiaries. We recog nized $3.9 million ($1.5 million for stock options and $2.4 million for RSUs) and $2.8 million ($1.3 million for stock options and $1.5 million for RSUs) of share-based compensation expense for these awards in our Consolidated Statements of Operations and Comprehensive Income, in “Selling, general and administrative expenses,” for the three months ended March 31, 2022 and 2021, respectively. Stock Options Stock options generally vest ratably over a period of three Number of Shares Weighted- average Exercise Price Outstanding stock options at December 31, 2021 2,423,256 $ 23.02 Granted 1,401,535 20.03 Forfeited (33,586) 22.97 Exercised — — Outstanding stock options at March 31, 2022 3,791,205 $ 21.92 RSUs RSUs generally vest ratably over a period of one Number of Shares Weighted- average Grant Date Fair Value Unvested at December 31, 2021 640,122 $ 23.19 Granted 820,666 20.65 Forfeited (18,223) 23.04 Vested (2,713) 26.10 Unvested at March 31, 2022 1,439,852 $ 21.74

Earnings Per Share

Earnings Per Share - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings Per Share [Abstract]
Earnings Per Share	Earnings Per Share Basic earnings per share represents the amount of income attributable to each common share outstanding. Diluted earnings per share represents the amount of income attributable to each common share outstanding adjusted for the effects of potentially dilutive common shares. Potentially dilutive common shares include stock options and other stock-based awards. In the periods where the effect would be antidilutive, potentially dilutive common shares are excluded from the calculation of diluted earnings per share. In periods in which the Company has net income, earnings per share is calculated using the two-class method. This method is required as unvested restricted stock distributed in respect of pre-IPO Class B-1 and B-2 awards have the right to receive non-forfeitable dividends or dividend equivalents if the Company were to declare dividends on its common stock. Pursuant to the two-class method, earnings for each period are allocated on a pro-rata basis to common stockholders and unvested pre-IPO Class B-1 and B-2 restricted stock awards. Diluted earnings per share is computed using the more dilutive of (a) the two-class method, or (b) treasury stock method, as applicable, to the potentially dilutive instruments. Our basic and diluted earnings per common share are calculated as follows: Three Months Ended in thousands of U.S. dollars and share amounts (except per share amounts) March 31, March 31, Earnings: Net income $ 30,641 $ 11,065 Less: Net income attributable to noncontrolling interests — 223 Less: Allocation to participating securities 338 157 Net income attributable to Sotera Health Company common shareholders $ 30,303 $ 10,685 Weighted Average Common Shares: Weighted-average common shares outstanding - basic 279,829 278,827 Dilutive effect of potential common shares 79 141 Weighted-average common shares outstanding - diluted 279,908 278,968 Earnings per Common Share: Net income attributable to Sotera Health Company common shareholders - basic $ 0.11 $ 0.04 Net income attributable to Sotera Health Company common shareholders - diluted 0.11 0.04 Diluted earnings per share does not consider the following potential common shares as the effect would be anti-dilutive: Three Months Ended in thousands of share amounts March 31, March 31, Stock options 2,889 2,400 RSUs 172 4 Total anti-dilutive securities 3,061 2,404
Total net revenues	$ 236,754	$ 212,148

Commitment and Contingencies

Commitment and Contingencies	3 Months Ended
	Mar. 31, 2022
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	Commitments and Contingencies From time to time, we may be subject to various lawsuits and other claims, as well as gain contingencies, in the ordinary course of our business. In addition, from time to time, we receive communications from government or regulatory agencies concerning investigations or allegations of noncompliance with laws or regulations in jurisdictions in which we operate. We establish reserves for specific liabilities in connection with regulatory and legal actions that we determine to be both probable and reasonably estimable. No material amounts have been accrued in our consolidated financial statements with respect to any loss contingencies. In certain of the matters described below, we are not able to make a reasonable estimate of any liability because of the uncertainties related to the outcome and/or the amount or range of loss. While it is not possible to determine the ultimate disposition of each of these matters, we do not expect that the ultimate resolution of pending regulatory and legal matters in future periods, including the matters described below, will have a material effect on our financial condition or results of operations. Despite the above, the Company may incur material defense and settlement costs, diversion of management resources and other adverse effects on our business, financial condition, or results of operations. Business Interruption Claim (NRU Outage) Nordion, due to the shutdown of Atomic Energy of Canada Limited's (“AECL”) NRU reactor in 2009, suffered a cessation of supply of radioisotopes and business interruption loss. Nordion, by Statement of Claim dated October 22, 2010, issued in Ontario Superior Court an action against an insurer, claiming $25.0 million USD in losses resulting from the shutdown of AECL’s reactor and its inability to supply radioisotopes through the specified period of approximately 15 months. The insurer objected to Nordion’s claim. On March 30, 2020, Nordion received a favorable judgment in the amount of $25.0 million USD, plus pre-judgment interest, for a total judgment value of $39.8 million USD, or $56.4 million CAD based on exchange rates approved by the trial court. In addition, costs and disbursements were assessed and awarded by the trial court in favor of Nordion in the approximate amount of $1.3 million CAD ($1.0 million USD). The insurer appealed the judgment, and on September 3, 2021 the Court of Appeal ruled in favor of the insurer denying insurance coverage to Nordion, and awarding costs and disbursements (in both the Trial Court and Court of Appeal) to the insurer, assessed at $0.6 million CAD ($0.5 million USD). Nordion's October 21, 2021 Application for Leave to Appeal was denied by the Supreme Court of Canada on March 31, 2022. Ethylene Oxide Tort Litigation Sterigenics and other medical supply sterilization companies have been subjected to personal injury and related tort lawsuits alleging various injuries caused by low-level environmental exposure to EO emissions from sterilization facilities. Those lawsuits, as detailed further below, are individual claims, as opposed to class actions. Illinois Approximately 780 plaintiffs have filed lawsuits against subsidiaries of the Company and other parties, alleging personal injuries including cancer and other diseases, or wrongful death, resulting from purported emissions and releases of EO from Sterigenics U.S., LLC’s former Willowbrook facility. Additional derivative claims are alleged on behalf of other individuals related to some of these personal injury plaintiffs. Each plaintiff seeks damages in an amount to be determined by the trier of fact. The lawsuits were consolidated for pre-trial purposes by the Cook County Circuit Court, Illinois (the “Consolidated Case”). Plaintiffs have not yet made any specific damages claims. Fact discovery in the Consolidated Case concluded on February 1, 2022. Trials in three of the individual cases included in the Consolidated Case have been scheduled for July 18, 2022, September 12, 2022 and November 7, 2022. Plaintiffs in those three cases have filed motions for leave to amend their claims to seek punitive damage awards against subsidiaries of the Company and other parties. A hearing on those motions is scheduled for May 23, 2022. The next five individual trials are scheduled to occur consecutively, beginning on January 17, 2023. Additional 2023 trial dates are expected to be announced on July 18, 2022. Georgia Since August 17, 2020, approximately 300 plaintiffs have filed lawsuits against subsidiaries of the Company and other parties in the State Court of Cobb County, Georgia and the State Court of Gwinnett County, Georgia alleging that they suffered personal injuries resulting from emissions and releases of EO from Sterigenics’ Atlanta facility. Additional derivative claims are alleged on behalf of other individuals related to some of these personal injury plaintiffs. Our subsidiaries are also defendants in two lawsuits alleging that the Atlanta facility has devalued and harmed plaintiffs’ use of real properties they own in Smyrna, Georgia and caused other damages. These personal injury and property devaluation plaintiffs seek various forms of relief including damages. All but two of the personal injury lawsuits pending in Cobb County have been consolidated for pretrial purposes. The Court has entered a phased case management schedule for a “pool” of ten of the consolidated cases by which threshold general causation issues will be decided in Phase 1, followed by specific causation issues in Phase 2 as to any of the pooled cases that survive Phase 1. The Court has stayed the remainder of the consolidated personal injury cases pending in Cobb County. One personal injury case is pending in Gwinnett County and is scheduled for trial in June 2023. The remaining two personal injury cases and two property devaluation cases are in various stages of pleadings and motions practice and fact discovery. Georgia Facility Operations Litigation In October 2019, while Sterigenics had voluntarily suspended the facility’s operations to install emissions reduction enhancements at its Atlanta facility, Cobb County, Georgia officials asserted that the facility had an incorrect “certificate of occupancy” and could not resume operations without obtaining a new certificate of occupancy after a third-party code compliance review. On March 30, 2020 Sterigenics filed suit against Cobb County, Georgia and certain of its officials for wrongfully interfering with operations of the facility. On April 1, 2020 Sterigenics won a Temporary Restraining Order prohibiting Cobb County officials from interfering with the facility’s normal operations, which relief has been extended until entry of a final judgment in the case. The parties are conducting discovery, which is scheduled to end in August 2022. A settlement conference is scheduled to be held by June 17, 2022. New Mexico Attorney General Litigation On December 22, 2020, the New Mexico Attorney General filed a lawsuit in the Third Judicial District Court, Doña Ana County, New Mexico against the Company and certain subsidiaries alleging that emissions of EO from Sterigenics’ sterilization facility in Santa Teresa, New Mexico have deteriorated the air quality in Santa Teresa and surrounding communities and materially contributed to increased health risks suffered by residents of those communities. The Complaint asserts claims for public nuisance, negligence, strict liability, violations of New Mexico’s Public Nuisance Statute and Unfair Practices Act and seeks various forms of relief including a temporary restraining order and preliminary injunctive relief and damages. On June 29, 2021, the Court entered an Order Granting Preliminary Injunction (the “Order”). The Order does not require closure of the facility, but prohibits Sterigenics from allowing any uncontrolled emission or release of EO from the facility. On December 20, 2021 the Court entered an order identifying a protocol to monitor Sterigenics’ compliance with the Order. A motion challenging the Court’s jurisdiction over the Company and certain other defendants has been held in abeyance until the completion of jurisdictional discovery, and all other motions to dismiss have been denied. The parties are conducting fact discovery. * * *

Financial Instruments and Finan

Financial Instruments and Financial Risk	3 Months Ended
	Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Financial Instruments and Financial Risk	Financial Instruments and Financial Risk Derivative Instruments We do not use derivatives for trading or speculative purposes and are not a party to leveraged derivatives. Derivatives Designated in Hedge Relationships From time to time, the Company utilizes interest rate derivatives designated in hedge relationships to manage interest rate risk associated with our variable rate borrowings. These instruments are measured at fair value with changes in fair value recorded as a component of “Accumulated other comprehensive income (loss)” on our Consolidated Balance Sheets. In October 2021, we entered into two interest rate cap agreements with a combined notional amount of $1,000.0 million for a total option premium of $1.8 million. Both interest rate caps have a forward start date of December 31, 2022 and expire on July 31, 2023. These interest rate caps are designated as cash flow hedges and are designed to hedge the variability of cash flows attributable to changes in LIBOR (or its successor), the benchmark interest rate being hedged, by limiting our cash flow exposure related to the LIBOR base rate under a portion of our variable rate borrowings to 1.0%. Derivatives Not Designated in Hedge Relationships Additionally, from time to time, the Company enters into interest rate caps to manage economic risks associated with our variable rate borrowings that are not designated in hedge relationships. These instruments are recorded at fair value on the Consolidated Balance Sheets, with any changes in the value being recorded in “Interest expense, net” in the Consolidated Statements of Operations and Comprehensive Income. In June 2020, SHH entered into two interest rate cap agreements with notional amounts of $1,000.0 million and $500.0 million, respectively, for a total option premium of $0.3 million. These instruments were initially scheduled to terminate on August 31, 2021 and February 28, 2022, respectively. The interest rate caps limited our cash flow exposure related to the LIBOR base rate under a portion of our variable rate borrowings to 1.0%. In February 2021, we amended the two interest rate cap agreements referenced above to reduce the strike rate from 1.0% to 0.5%, and extend the termination date of the $1,000.0 million notional cap to September 30, 2021. Premiums paid to amend the interest rate caps were immaterial. We also entered into two additional interest rate cap agreements in February 2021 with a combined notional amount of $1,000.0 million, for a total option premium of $0.4 million. These instruments became effective September 30, 2021, and will terminate on December 31, 2022. The amended and new interest rate caps limit our cash flow exposure related to LIBOR under a portion of our variable rate borrowings to 0.5%. The Company also entered into foreign currency forward contracts to manage foreign currency exchange rate risk of our intercompany loans in certain of our international subsidiaries. The foreign currency forward contracts expire on a monthly basis. The fair value of the outstanding foreign currency forward contracts was zero as of March 31, 2022 and December 31, 2021, respectively. Embedded Derivatives We have embedded derivatives in certain of our customer and supply contracts as a result of the currency of the contract being different from the functional currency of the parties involved. Changes in the fair value of the embedded derivatives are recognized in “Other income, net” in the Consolidated Statements of Operations and Comprehensive Income. The following table provides a summary of the notional and fair values of our derivative instruments: March 31, 2022 December 31, 2021 (in U.S. Dollars; notional in millions, fair value in thousands) Fair Value Fair Value Notional Derivative Derivative Notional Derivative Derivative Derivatives designated as hedging instruments Interest rate caps $ 1,000.0 (a) $ 10,610 — $ 1,000.0 $ 2,322 — Derivatives not designated as hedging instruments Interest rate caps 1,000.0 8,000 — 1,500.0 1,654 — Embedded derivatives 193.0 (b) 1,842 308 144.4 496 — Total $ 2,193.0 $ 20,452 $ 308 $ 2,644.4 $ 4,472 $ — (a) $1,000.0 million notional amount of interest rate caps designated as hedging instruments have a forward start date beginning on December 31, 2022. (b) Represents the total notional amounts for certain of the Company’s supply and sales contracts accounted for as embedded derivatives. Embedded derivative assets and interest rate caps are included in “Prepaid expenses and other current assets” and "Other Assets," respectively, on our Consolidated Balance Sheets. Embedded derivative liabilities are included in “Accrued liabilities” on the Consolidated Balance Sheets. The following tables summarize the activities of our derivative instruments for the periods presented, and the line item they are recorded in in the Consolidated Statements of Operations and Comprehensive Income: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Unrealized (gain) loss on interest rate derivatives recorded in interest expense, net $ (6,346) $ 90 Unrealized gain on embedded derivatives recorded in other income, net (1,018) (853) Realized gain on foreign currency forward contracts recorded in foreign exchange (gain) loss (1,530) (2,374) The following table summarizes the net gains (losses) on our cash flow hedges recognized in “Other comprehensive income (loss)” during the period. (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Unrealized gain on interest rate derivatives recorded in other comprehensive income, net of tax $ 6,179 $ — We expect to reclassify approximately $3.1 million of after-tax net gains on derivative instruments from accumulated other comprehensive income to income during the next 12 months associated with our cash flow hedges. Credit Risk Certain of our financial assets, including cash and cash equivalents, are exposed to credit risk. We are also exposed, in our normal course of business, to credit risk from our customers. As of March 31, 2022 and December 31, 2021, accounts receivable was net of an allowance for uncollectible accounts of $1.5 million and $1.3 million, respectively. Credit risk on financial instruments arises from the potential for counterparties to default on their contractual obligations to us. We are exposed to credit risk in the event of non-performance, but do not anticipate non-performance by any of the counterparties to our financial instruments. We limit our credit risk by dealing with counterparties that are considered to be of high credit quality. In the event of non-performance by counterparties, the carrying value of our financial instruments represents the maximum amount of loss that would be incurred. Our credit team evaluates and regularly monitors changes in the credit risk of our customers. We routinely assess the collectability of accounts receivable and maintain an adequate allowance for uncollectible accounts to address potential credit losses. The process includes a review of customer financial information and credit ratings, current market conditions as well as the expected future economic conditions that may impact the collection of trade receivables. We regularly review our customers' past due amounts through an analysis of aged accounts receivables, specific customer past due aging amounts, and the history of trade receivables written off. Upon concluding that a receivable balance is not collectible, the balance is written off against the allowance for uncollectible accounts. Fair Value Hierarchy The fair value of our financial instruments is the price that would be received to sell an asset or paid to transfer a liability in an orderly transaction between market participants at the measurement date. The valuation techniques we would use to determine such fair values are described as follows: Level 1—fair values determined by inputs utilizing quoted prices in active markets for identical assets or liabilities; Level 2—fair values based on observable inputs other than quoted prices included in Level 1, such as quoted prices for similar assets and liabilities in active markets, quoted prices for identical or similar assets and liabilities in markets that are not active, or other inputs that are observable; Level 3—fair values determined by unobservable inputs reflecting our own assumptions, consistent with reasonably available assumptions made by other market participants. The following table discloses the fair value of our financial assets and liabilities: As of March 31, 2022 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Derivative assets - interest rate caps $ 10,610 $ — $ 10,610 $ — Derivatives not designated as hedging instruments (b) Derivative assets - interest rate caps 8,000 — 8,000 — Embedded derivative assets 1,842 — 1,842 — Embedded derivative liabilities 308 — 308 — Long-Term Debt (c) Term loan, due 2026 1,744,096 — 1,744,411 — Other long-term debt 445 — 445 — Finance Lease Obligations (with current portion) (d) 41,356 — 41,356 — As of December 31, 2021 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Derivative assets - interest rate caps $ 2,322 $ — $ 2,322 $ — Derivatives not designated as hedging instruments (b) Derivative assets - interest rate caps 1,654 — 1,654 — Embedded derivative assets 496 — 496 — Long-Term Debt (c) Term loan, due 2026 1,743,090 — 1,754,285 — Other long-term debt 444 — 444 — Finance Lease Obligations (with current portion) (d) 42,037 — 42,037 — (a) Derivatives designated as hedging instruments are measured at fair value with changes in fair value recorded as a component of accumulated other comprehensive income (loss). Interest rate caps are valued using pricing models that incorporate observable market inputs including interest rate and yield curves. (b) Derivatives t hat are not designated as hedging instruments are measured at fair value with gains or losses recognized immediately in the Consolidated Statements of Operations and Comprehensive Income. Interest rate caps are valued using pricing models that incorporate observable market inputs including interest rate and yield curves. Embedded derivatives are valued using internally developed models that rely on observable market inputs including foreign currency forward curves. (c) Carrying amounts of long-term debt instruments are reported net of discounts and debt issuance costs. The estimated fair value of these instruments is based on quoted prices for the Term Loan due 2026 in inactive markets as provided by an independent fixed income security pricing service. Fair value approximates carrying value for “Other long-term debt.” (d) Fair value approximates carrying value.

Segment Information

Segment Information	3 Months Ended
	Mar. 31, 2022
Segment Reporting [Abstract]
Segment Information	Segment Information We identify our operating segments based on the way we manage, evaluate and internally report our business activities for purposes of allocating resources and assessing performance. We have three reportable segments: Sterigenics, Nordion and Nelson Labs. We have determined our reportable segments based upon an assessment of organizational structure, service types, and internally prepared financial statements. Our chief operating decision maker evaluates performance and allocates resources based on net revenues and segment income after the elimination of intercompany activities. The accounting policies of our reportable segments are the same as those described in Note 1, “Significant Accounting Policies” of our 2021 Form 10-K. Sterigenics Sterigenics provides outsourced terminal sterilization and irradiation services for the medical device, pharmaceutical, food safety and advanced applications markets using three major technologies: gamma irradiation, EO processing and E-beam irradiation. Nordion Nordion is a leading global provider of Co-60 used in the sterilization and irradiation processes for the medical device, pharmaceutical, food safety, and high-performance materials industries, as well as in the treatment of cancer. In addition, Nordion is a leading global provider of gamma irradiation systems. Nelson Labs Nelson Labs provides outsourced microbiological and analytical chemistry testing and advisory services for the medical device and biopharmaceutical industries. For the three months ended March 31, 2022, five customers reported within the Nordion segment individually represented 10% or more of the segment’s total net revenues. These customers represented 15.7%, 14.4%, 13.9%, 12.2%, and 11.9% of the total segment’s external net revenues for the three months ended March 31, 2022. For the three months ended March 31, 2021, three customers reported within the Nordion segment individually represented 10% or more of the segment's total net revenues. These customers represented 23.7%, 20.0% and 12.2% of the total segment's external net revenues for the three months ended March 31, 2021. (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Segment revenues (a) Sterigenics $ 149,462 $ 131,151 Nordion 34,002 25,918 Nelson Labs 53,290 55,079 Total net revenues $ 236,754 $ 212,148 Segment income (b) Sterigenics $ 79,403 $ 68,461 Nordion 18,903 13,786 Nelson Labs 17,043 23,070 Total segment income $ 115,349 $ 105,317 (a) Revenues are reported net of intersegment sales. Our Nordion segment recognized $15.5 million and $10.5 million in revenues from sales to our Sterigenics segment for the three months ended March 31, 2022 and 2021, respectively, that is not reflected in net revenues in the table above. Intersegment sales for Sterigenics and Nelson Labs are immaterial for both periods. (b) Segment income is only provided on a net basis to the chief operating decision maker and is reported net of intersegment profits. Corporate operating expenses for executive management, accounting, information technology, legal, human resources, treasury, corporate development, tax, purchasing, and marketing not directly incurred by a segment are allocated to the segments based on total net revenue. Corporate operating expenses that are directly incurred by a segment are reflected in each segment’s income. Capital expenditures by segment for the three months ended March 31, 2022 and 2021 were as follows: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Sterigenics $ 25,221 $ 19,514 Nordion 7,090 489 Nelson Labs 3,235 939 Total capital expenditures $ 35,546 $ 20,942 Total assets and depreciation and amortization expense by segment are not readily available and are not reported separately to the chief operating decision maker. A reconciliation of segment income to consolidated income before taxes is as follows: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Segment income $ 115,349 $ 105,317 Less adjustments: Interest expense, net (a) 16,750 21,282 Depreciation and amortization (b) 36,049 37,661 Share-based compensation (c) 4,538 3,449 Gain on foreign currency and derivatives not designated as hedging instruments, net (d) (6,552) (336) Acquisition and divestiture related charges, net (e) (160) (185) Business optimization project expenses (f) 104 261 Plant closure expenses (g) 671 542 Loss on extinguishment of debt (h) — 14,312 Professional services relating to EO sterilization facilities (i) 18,059 13,399 Accretion of asset retirement obligation (j) 520 551 COVID-19 expenses (k) 103 299 Consolidated income before taxes $ 45,267 $ 14,082 (a) The three months ended March 31, 2022 excludes $6.3 million of unrealized gains on interest rate derivatives not designated as hedging instruments. (b) Includes depreciation of Co-60 held at gamma irradiation sites. (c) Represents non-cash share-based compensation expense. (d) Represents the effects of (i) fluctuations in foreign currency exchange rates, (ii) non-cash mark-to-fair value of embedded derivatives relating to certain customer and supply contracts at Nordion, and (iii) unrealized gains on interest rate caps not designated as hedging instruments. (e) Represents (i) certain direct and incremental costs related to the acquisitions of RCA, the noncontrolling interests in our China subsidiaries, BioScience Labs in 2021, the first quarter 2021 gain on the mandatorily redeemable noncontrolling interest in Nelson Labs Fairfield (as described in Note 4, “Acquisitions”), and certain related integration efforts as a result of those acquisitions, (ii) the earnings impact of fair value adjustments (excluding those recognized within amortization expense) resulting from the businesses acquired, and (iii) transition services income and non-cash deferred lease income associated with the terms of the divestiture of the Medical Isotopes business in 2018. (f) Represents professional fees, contract termination and exit costs, severance and other payroll costs, and other costs associated with business optimization and cost savings projects relating to the integration of acquisitions, operating structure realignment and other process enhancement projects. (g) Represents professional fees, severance and other payroll costs, and other costs including ongoing lease and utility expenses associated with the closure of the Willowbrook, Illinois facility. (h) Represents expenses incurred in connection with the repricing of our Term Loan in January 2021 including accelerated amortization of prior debt issuance and discount costs. (i) Represents professional fees related to litigation associated with our EO sterilization facilities and other related professional fees. See Note 16, “Commitments and Contingencies” . (j) Represents non-cash accretion of asset retirement obligations related to Co-60 and gamma processing facilities, which are based on estimated site remediation costs for any future decommissioning of these facilities (without regard for whether the decommissioning services would be performed by employees of Nordion, instead of by a third party) and are accreted over the life of the asset. (k) Represents non-recurring costs associated with the COVID-19 pandemic, including incremental costs to implement workplace health and safety measures.

Basis of Presentation (Policies

Basis of Presentation (Policies)	3 Months Ended
	Mar. 31, 2022
Accounting Policies [Abstract]
Use of Estimates	Use of Estimates – In preparing our consolidated financial statements in conformity with U.S. Generally Accepted Accounting Principles (“GAAP”), we make estimates and assumptions that affect the amounts reported and the accompanying notes. We regularly evaluate the estimates and assumptions used and revise them as new information becomes available. Actual results may vary from those estimates.
Recent Accounting Standards	Adoption of Accounting Standard Updates Effective January 1, 2022, we adopted Accounting Standards Update (“ASU”) 2016-13, Financial Instruments – Credit Losses (“ASU 2016-13”): Measurement of Credit Losses on Financial Instruments, and the subsequently issued additional guidance that modified ASU 2016-13 which was originally issued by the Financial Accounting Standards Board (“FASB”) in June 2016. The standard requires an entity to change its accounting approach in determining impairment of certain financial instruments, including trade receivables, from an “incurred loss” to a “current expected credit loss” model. The adoption of this standard did not have a material impact on our consolidated financial statements and disclosures. Effective January 1, 2022, we adopted ASU 2019-12 - Income Taxes (Topic 740): Simplifying the Accounting for Income Taxes which was issued by the FASB in December 2019. The standard simplifies the accounting for income taxes and makes a number of changes meant to add or clarify guidance on accounting for income taxes. The adoption of this standard did not have a material impact on our consolidated financial statements and disclosures. ASU’s Issued But Not Yet Adopted In October 2021, the FASB issued ASU 2021-08 - Business Combinations (Topic 805): Accounting for Contract Assets and Contract Liabilities from Contracts with Customers (“ASU 2021-08”). The amendments in ASU 2021-08 require that an acquiring entity recognize and measure contract assets and contract liabilities acquired in a business combination in accordance with Accounting Standards Codification (“ASC”) Topic 606, Revenue from Contract with Customers (“ASC Topic 606”). At the acquisition date, an acquirer should account for the related revenue contracts in accordance with ASC Topic 606 as if it had originated the contracts. For public business entities, these amendments are effective for fiscal years beginning after December 15, 2022, including interim periods within those fiscal years. We are currently assessing the effect that ASU 2021-08 will have on our financial position, results of operations, and disclosures.

Revenue Recognition (Tables)

Revenue Recognition (Tables)	3 Months Ended
	Mar. 31, 2022
Revenue from Contract with Customer [Abstract]
Schedule of Disaggregation of Revenue	The following table shows disaggregated net revenues from contracts with external customers by timing of revenue and by segment for the three months ended March 31, 2022 and 2021: (thousands of U.S. dollars) Three Months Ended March 31, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 149,462 $ 33,285 $ — $ 182,747 Over time — 717 53,290 54,007 Total $ 149,462 $ 34,002 $ 53,290 $ 236,754 (thousands of U.S. dollars) Three Months Ended March 31, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 131,151 $ 25,918 $ — $ 157,069 Over time — — 55,079 55,079 Total $ 131,151 $ 25,918 $ 55,079 $ 212,148

Inventories (Tables)

Inventories (Tables)	3 Months Ended
	Mar. 31, 2022
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Raw materials and supplies $ 32,451 $ 41,514 Work-in-process 758 3,919 Finished goods 12,618 8,979 45,827 54,412 Reserve for excess and obsolete inventory (126) (124) Inventories, net $ 45,701 $ 54,288

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	3 Months Ended
	Mar. 31, 2022
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Schedule of Deferred Costs, Capitalized, Prepaid, and Other Assets	Prepaid expenses and other current assets consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Prepaid taxes $ 26,752 $ 24,937 Prepaid business insurance 8,107 10,707 Prepaid rent 1,203 920 Customer contract assets 18,547 15,565 Insurance and indemnification receivables 3,805 3,144 Current deposits 493 623 Prepaid maintenance contracts 336 279 Value added tax receivable 1,500 2,512 Prepaid software licensing 1,428 2,055 Stock supplies 3,587 3,374 Embedded derivative assets 1,842 496 Other 16,356 7,311 Prepaid expenses and other current assets $ 83,956 $ 71,923

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	3 Months Ended
	Mar. 31, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Changes to goodwill during the three months ended March 31, 2022 were as follows: (thousands of U.S. dollars) Sterigenics Nordion Nelson Labs Total Goodwill at December 31, 2021 $ 660,743 $ 288,905 $ 170,672 $ 1,120,320 RCA acquisition measurement period adjustments — — 56 56 Changes due to foreign currency exchange rates 1,733 4,423 (704) 5,452 Goodwill at March 31, 2022 $ 662,476 $ 293,328 $ 170,024 $ 1,125,828
Schedule of Acquired Finite-Lived Intangible Assets	Other intangible assets consisted of the following: (thousands of U.S. dollars) Gross Carrying Amount Accumulated Amortization As of March 31, 2022 Finite-lived intangible assets Customer relationships $ 668,034 $ 380,341 Proprietary technology 89,037 46,268 Trade names 170 139 Land-use rights 9,773 1,650 Sealed source and supply agreements 245,334 114,818 Other 6,483 2,628 Total finite-lived intangible assets 1,018,831 545,844 Indefinite-lived intangible assets Regulatory licenses and other (a) 83,375 — Trade names / trademarks 25,782 — Total indefinite-lived intangible assets 109,157 — Total $ 1,127,988 $ 545,844 As of December 31, 2021 Gross Carrying Amount Accumulated Amortization Finite-lived intangible assets Customer relationships $ 668,628 $ 365,935 Proprietary technology 88,826 44,866 Trade names 145 116 Land-use rights 9,744 1,586 Sealed source and supply agreements 241,611 109,838 Other 6,454 2,166 Total finite-lived intangible assets 1,015,408 524,507 Indefinite-lived intangible assets Regulatory licenses and other (a) 82,110 — Trade names / trademarks 25,833 — Total indefinite-lived intangible assets 107,943 — Total $ 1,123,351 $ 524,507 (a) Includes certain transportation certifications, a class 1B nuclear license and other intangibles related to obtaining such licensure. These assets are considered indefinite-lived as the decision for renewal by the Canadian Nuclear Safety Commission is highly based on a licensee’s previous assessments, reported incidents, and annual compliance and inspection results. New applications for license can take a significant amount of time and cost; whereas an existing licensee with a historical record of compliance and current operating conditions more than likely ensures renewal for another 10 year license period as Nordion has demonstrated over its 75 years of history.
Schedule of Acquired Indefinite-lived Intangible Assets	Other intangible assets consisted of the following: (thousands of U.S. dollars) Gross Carrying Amount Accumulated Amortization As of March 31, 2022 Finite-lived intangible assets Customer relationships $ 668,034 $ 380,341 Proprietary technology 89,037 46,268 Trade names 170 139 Land-use rights 9,773 1,650 Sealed source and supply agreements 245,334 114,818 Other 6,483 2,628 Total finite-lived intangible assets 1,018,831 545,844 Indefinite-lived intangible assets Regulatory licenses and other (a) 83,375 — Trade names / trademarks 25,782 — Total indefinite-lived intangible assets 109,157 — Total $ 1,127,988 $ 545,844 As of December 31, 2021 Gross Carrying Amount Accumulated Amortization Finite-lived intangible assets Customer relationships $ 668,628 $ 365,935 Proprietary technology 88,826 44,866 Trade names 145 116 Land-use rights 9,744 1,586 Sealed source and supply agreements 241,611 109,838 Other 6,454 2,166 Total finite-lived intangible assets 1,015,408 524,507 Indefinite-lived intangible assets Regulatory licenses and other (a) 82,110 — Trade names / trademarks 25,833 — Total indefinite-lived intangible assets 107,943 — Total $ 1,123,351 $ 524,507 (a) Includes certain transportation certifications, a class 1B nuclear license and other intangibles related to obtaining such licensure. These assets are considered indefinite-lived as the decision for renewal by the Canadian Nuclear Safety Commission is highly based on a licensee’s previous assessments, reported incidents, and annual compliance and inspection results. New applications for license can take a significant amount of time and cost; whereas an existing licensee with a historical record of compliance and current operating conditions more than likely ensures renewal for another 10 year license period as Nordion has demonstrated over its 75 years of history.
Schedule of Finite-Lived Intangible Assets, Future Amortization Expense	The estimated aggregate amortization expense for finite-lived intangible assets for each of the next five years and thereafter is as follows: (thousands of U.S. dollars) For the remainder of 2022 $ 62,157 2023 82,016 2024 81,237 2025 43,437 2026 23,181 Thereafter 180,959 Total $ 472,987

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	3 Months Ended
	Mar. 31, 2022
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Accrued employee compensation $ 29,391 $ 33,334 Legal reserves 3,134 3,259 Accrued interest expense 10,132 10,755 Embedded derivatives 308 — Professional fees 7,708 4,314 Accrued utilities 1,833 1,797 Insurance accrual 1,407 2,068 Accrued taxes 2,333 2,209 Other 4,213 4,125 Accrued liabilities $ 60,459 $ 61,861

Long-Term Debt (Tables)

Long-Term Debt (Tables)	3 Months Ended
	Mar. 31, 2022
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long-term debt consisted of the following: (thousands of U.S. dollars) March 31, 2022 December 31, 2021 Term loan, due 2026 $ 1,763,100 $ 1,763,100 Other long-term debt 450 450 Total long-term debt 1,763,550 1,763,550 Less unamortized debt issuance costs and debt discounts (19,009) (20,016) Total long-term debt, less debt issuance costs and debt discounts $ 1,744,541 $ 1,743,534
Schedule of Maturities of Long-term Debt	Aggregate maturities of the Company’s long-term debt, excluding debt discounts, as of March 31, 2022, are as follows: (thousands of U.S. dollars) 2022 $ — 2023 450 2024 — 2025 — 2026 1,763,100 Thereafter — Total $ 1,763,550

Employee Benefits (Tables)

Employee Benefits (Tables)	3 Months Ended
	Mar. 31, 2022
Postemployment Benefits [Abstract]
Schedule of Net Benefit Costs	The components of net periodic pension cost for the defined benefit plans for the three months ended March 31, 2022 and 2021 were as follows: Three Months Ended March 31, (thousands of U.S. dollars) 2022 2021 Service cost $ 249 $ 298 Interest cost 1,903 1,613 Expected return on plan assets (3,704) (3,557) Amortization of net actuarial loss — 267 Net periodic benefit $ (1,552) $ (1,379) Three Months Ended March 31, (thousands of U.S. dollars) 2022 2021 Service cost $ 4 $ 7 Interest cost 65 59 Amortization of net actuarial (gain) loss (2) 8 Net periodic benefit cost $ 67 $ 74

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	3 Months Ended
	Mar. 31, 2022
Equity [Abstract]
Schedule of Accumulated Other Comprehensive Income (Loss)	Changes in our accumulated other comprehensive income (loss) balances, net of applicable tax, were as follows: (thousands of U.S. dollars) Defined Benefit Plans Foreign Currency Translation Interest Rate Swaps Total Beginning balance – January 1, 2022 $ (17,581) $ (66,389) $ 404 $ (83,566) Other comprehensive income (loss) before reclassifications (272) 14,975 6,179 20,882 Amounts reclassified from accumulated other comprehensive income (loss) (2) (a) — — (b) (2) Net current-period other comprehensive income (loss) (274) 14,975 6,179 20,880 Ending balance – March 31, 2022 $ (17,855) $ (51,414) $ 6,583 $ (62,686) Beginning balance – January 1, 2021 $ (44,143) $ (49,699) $ — $ (93,842) Other comprehensive income (loss) before reclassifications (524) (3,071) — (3,595) Amounts reclassified from accumulated other comprehensive income (loss) 275 (a) — — 275 Net current-period other comprehensive income (loss) (249) (3,071) — (3,320) Ending balance – March 31, 2021 $ (44,392) $ (52,770) $ — $ (97,162) (a) For defined benefit pension plans, amounts reclassified from accumulated other comprehensive income (loss) are recorded to “Other income, net” within the Consolidated Statements of Operations and Comprehensive Income. (b) For interest rate derivatives, amounts reclassified from accumulated other comprehensive income (loss) are recorded to “Interest expense, net” within the Consolidated Statements of Operations and Comprehensive Income.

Share-Based Compensation (Table

Share-Based Compensation (Tables)	3 Months Ended
	Mar. 31, 2022
Share-based Payment Arrangement [Abstract]
Schedule of Restricted Stock Activity	A summary of the activity for the three months ended March 31, 2022 related to the restricted stock awards distributed to the Company service providers in respect of the pre-IPO awards (Class B-1 and B-2 Units) is presented below: Restricted Stock - Pre- IPO B-1 Restricted Stock - Pre- IPO B-2 Unvested at December 31, 2021 1,206,089 2,023,959 Forfeited (15,793) (40,616) Vested (144,713) — Unvested at March 31, 2022 1,045,583 1,983,343 Number of Shares Weighted- average Grant Date Fair Value Unvested at December 31, 2021 640,122 $ 23.19 Granted 820,666 20.65 Forfeited (18,223) 23.04 Vested (2,713) 26.10 Unvested at March 31, 2022 1,439,852 $ 21.74
Schedule of Stock Option Activity	The following table summarizes our stock option activity: Number of Shares Weighted- average Exercise Price Outstanding stock options at December 31, 2021 2,423,256 $ 23.02 Granted 1,401,535 20.03 Forfeited (33,586) 22.97 Exercised — — Outstanding stock options at March 31, 2022 3,791,205 $ 21.92

Earnings Per Share (Tables)

Earnings Per Share (Tables)	3 Months Ended
	Mar. 31, 2022
Earnings Per Share [Abstract]
Schedule of Earnings Per Share, Basic and Diluted	Our basic and diluted earnings per common share are calculated as follows: Three Months Ended in thousands of U.S. dollars and share amounts (except per share amounts) March 31, March 31, Earnings: Net income $ 30,641 $ 11,065 Less: Net income attributable to noncontrolling interests — 223 Less: Allocation to participating securities 338 157 Net income attributable to Sotera Health Company common shareholders $ 30,303 $ 10,685 Weighted Average Common Shares: Weighted-average common shares outstanding - basic 279,829 278,827 Dilutive effect of potential common shares 79 141 Weighted-average common shares outstanding - diluted 279,908 278,968 Earnings per Common Share: Net income attributable to Sotera Health Company common shareholders - basic $ 0.11 $ 0.04 Net income attributable to Sotera Health Company common shareholders - diluted 0.11 0.04
Schedule of Antidilutive Securities Excluded from Computation of Earnings Per Share	Diluted earnings per share does not consider the following potential common shares as the effect would be anti-dilutive: Three Months Ended in thousands of share amounts March 31, March 31, Stock options 2,889 2,400 RSUs 172 4 Total anti-dilutive securities 3,061 2,404

Financial Instruments and Fin_2

Financial Instruments and Financial Risk (Tables)	3 Months Ended
	Mar. 31, 2022
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Schedule of Derivative Instruments	The following table provides a summary of the notional and fair values of our derivative instruments: March 31, 2022 December 31, 2021 (in U.S. Dollars; notional in millions, fair value in thousands) Fair Value Fair Value Notional Derivative Derivative Notional Derivative Derivative Derivatives designated as hedging instruments Interest rate caps $ 1,000.0 (a) $ 10,610 — $ 1,000.0 $ 2,322 — Derivatives not designated as hedging instruments Interest rate caps 1,000.0 8,000 — 1,500.0 1,654 — Embedded derivatives 193.0 (b) 1,842 308 144.4 496 — Total $ 2,193.0 $ 20,452 $ 308 $ 2,644.4 $ 4,472 $ — (a) $1,000.0 million notional amount of interest rate caps designated as hedging instruments have a forward start date beginning on December 31, 2022. (b) Represents the total notional amounts for certain of the Company’s supply and sales contracts accounted for as embedded derivatives.
Schedule of Derivative Instruments, Gain (Loss)	The following tables summarize the activities of our derivative instruments for the periods presented, and the line item they are recorded in in the Consolidated Statements of Operations and Comprehensive Income: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Unrealized (gain) loss on interest rate derivatives recorded in interest expense, net $ (6,346) $ 90 Unrealized gain on embedded derivatives recorded in other income, net (1,018) (853) Realized gain on foreign currency forward contracts recorded in foreign exchange (gain) loss (1,530) (2,374) The following table summarizes the net gains (losses) on our cash flow hedges recognized in “Other comprehensive income (loss)” during the period. (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Unrealized gain on interest rate derivatives recorded in other comprehensive income, net of tax $ 6,179 $ —
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis	The following table discloses the fair value of our financial assets and liabilities: As of March 31, 2022 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Derivative assets - interest rate caps $ 10,610 $ — $ 10,610 $ — Derivatives not designated as hedging instruments (b) Derivative assets - interest rate caps 8,000 — 8,000 — Embedded derivative assets 1,842 — 1,842 — Embedded derivative liabilities 308 — 308 — Long-Term Debt (c) Term loan, due 2026 1,744,096 — 1,744,411 — Other long-term debt 445 — 445 — Finance Lease Obligations (with current portion) (d) 41,356 — 41,356 — As of December 31, 2021 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Derivative assets - interest rate caps $ 2,322 $ — $ 2,322 $ — Derivatives not designated as hedging instruments (b) Derivative assets - interest rate caps 1,654 — 1,654 — Embedded derivative assets 496 — 496 — Long-Term Debt (c) Term loan, due 2026 1,743,090 — 1,754,285 — Other long-term debt 444 — 444 — Finance Lease Obligations (with current portion) (d) 42,037 — 42,037 — (a) Derivatives designated as hedging instruments are measured at fair value with changes in fair value recorded as a component of accumulated other comprehensive income (loss). Interest rate caps are valued using pricing models that incorporate observable market inputs including interest rate and yield curves. (b) Derivatives t hat are not designated as hedging instruments are measured at fair value with gains or losses recognized immediately in the Consolidated Statements of Operations and Comprehensive Income. Interest rate caps are valued using pricing models that incorporate observable market inputs including interest rate and yield curves. Embedded derivatives are valued using internally developed models that rely on observable market inputs including foreign currency forward curves. (c) Carrying amounts of long-term debt instruments are reported net of discounts and debt issuance costs. The estimated fair value of these instruments is based on quoted prices for the Term Loan due 2026 in inactive markets as provided by an independent fixed income security pricing service. Fair value approximates carrying value for “Other long-term debt.” (d) Fair value approximates carrying value.

Segment Information (Tables)

Segment Information (Tables)	3 Months Ended
	Mar. 31, 2022
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	(thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Segment revenues (a) Sterigenics $ 149,462 $ 131,151 Nordion 34,002 25,918 Nelson Labs 53,290 55,079 Total net revenues $ 236,754 $ 212,148 Segment income (b) Sterigenics $ 79,403 $ 68,461 Nordion 18,903 13,786 Nelson Labs 17,043 23,070 Total segment income $ 115,349 $ 105,317 (a) Revenues are reported net of intersegment sales. Our Nordion segment recognized $15.5 million and $10.5 million in revenues from sales to our Sterigenics segment for the three months ended March 31, 2022 and 2021, respectively, that is not reflected in net revenues in the table above. Intersegment sales for Sterigenics and Nelson Labs are immaterial for both periods. (b) Segment income is only provided on a net basis to the chief operating decision maker and is reported net of intersegment profits. Capital expenditures by segment for the three months ended March 31, 2022 and 2021 were as follows: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Sterigenics $ 25,221 $ 19,514 Nordion 7,090 489 Nelson Labs 3,235 939 Total capital expenditures $ 35,546 $ 20,942
Schedule of Reconciliation of Operating Profit (Loss) from Segments to Consolidated	A reconciliation of segment income to consolidated income before taxes is as follows: (thousands of U.S. dollars) Three Months Ended March 31, 2022 2021 Segment income $ 115,349 $ 105,317 Less adjustments: Interest expense, net (a) 16,750 21,282 Depreciation and amortization (b) 36,049 37,661 Share-based compensation (c) 4,538 3,449 Gain on foreign currency and derivatives not designated as hedging instruments, net (d) (6,552) (336) Acquisition and divestiture related charges, net (e) (160) (185) Business optimization project expenses (f) 104 261 Plant closure expenses (g) 671 542 Loss on extinguishment of debt (h) — 14,312 Professional services relating to EO sterilization facilities (i) 18,059 13,399 Accretion of asset retirement obligation (j) 520 551 COVID-19 expenses (k) 103 299 Consolidated income before taxes $ 45,267 $ 14,082 (a) The three months ended March 31, 2022 excludes $6.3 million of unrealized gains on interest rate derivatives not designated as hedging instruments. (b) Includes depreciation of Co-60 held at gamma irradiation sites. (c) Represents non-cash share-based compensation expense. (d) Represents the effects of (i) fluctuations in foreign currency exchange rates, (ii) non-cash mark-to-fair value of embedded derivatives relating to certain customer and supply contracts at Nordion, and (iii) unrealized gains on interest rate caps not designated as hedging instruments. (e) Represents (i) certain direct and incremental costs related to the acquisitions of RCA, the noncontrolling interests in our China subsidiaries, BioScience Labs in 2021, the first quarter 2021 gain on the mandatorily redeemable noncontrolling interest in Nelson Labs Fairfield (as described in Note 4, “Acquisitions”), and certain related integration efforts as a result of those acquisitions, (ii) the earnings impact of fair value adjustments (excluding those recognized within amortization expense) resulting from the businesses acquired, and (iii) transition services income and non-cash deferred lease income associated with the terms of the divestiture of the Medical Isotopes business in 2018. (f) Represents professional fees, contract termination and exit costs, severance and other payroll costs, and other costs associated with business optimization and cost savings projects relating to the integration of acquisitions, operating structure realignment and other process enhancement projects. (g) Represents professional fees, severance and other payroll costs, and other costs including ongoing lease and utility expenses associated with the closure of the Willowbrook, Illinois facility. (h) Represents expenses incurred in connection with the repricing of our Term Loan in January 2021 including accelerated amortization of prior debt issuance and discount costs. (i) Represents professional fees related to litigation associated with our EO sterilization facilities and other related professional fees. See Note 16, “Commitments and Contingencies” . (j) Represents non-cash accretion of asset retirement obligations related to Co-60 and gamma processing facilities, which are based on estimated site remediation costs for any future decommissioning of these facilities (without regard for whether the decommissioning services would be performed by employees of Nordion, instead of by a third party) and are accreted over the life of the asset. (k) Represents non-recurring costs associated with the COVID-19 pandemic, including incremental costs to implement workplace health and safety measures.

Basis of Presentation (Details)

Basis of Presentation (Details)	May 18, 2021subsidiary	Mar. 31, 2022segment	Jun. 30, 2021subsidiary	Mar. 11, 2021	Jul. 31, 2020	Aug. 31, 2018
Accounting Policies [Abstract]
Number of operating segments		3
Number of reportable segments		3
Unnamed E-Beam Joint Venture | Iotron
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Ownership percentage					60.00%
Nelson Fairfield
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Interest acquired				15.00%		85.00%
China
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Number of subsidiaries with non-controlling interest | subsidiary	2		2
China | Subsidiary One
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percent of purchase of interest	15.00%		15.00%
China | Subsidiary Two
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percent of purchase of interest	33.00%		33.00%

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total net revenues	$ 236,754	$ 212,148
Customer contract assets	18,547		$ 15,565
Deferred revenue	12,928		$ 8,669
Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	182,747	157,069
Over time
Disaggregation of Revenue [Line Items]
Total net revenues	54,007	55,079
Sterigenics
Disaggregation of Revenue [Line Items]
Total net revenues	149,462	131,151
Sterigenics | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	149,462	131,151
Sterigenics | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	0	0
Nordion
Disaggregation of Revenue [Line Items]
Total net revenues	34,002	25,918
Nordion | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	33,285	25,918
Nordion | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	717	0
Nelson Labs
Disaggregation of Revenue [Line Items]
Total net revenues	53,290	55,079
Nelson Labs | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	0	0
Nelson Labs | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	$ 53,290	$ 55,079

Acquisitions (Details)

Acquisitions (Details) $ in Thousands	Nov. 04, 2021USD ($)	May 18, 2021USD ($)subsidiary	Mar. 11, 2021USD ($)	Mar. 08, 2021USD ($)	Aug. 21, 2020plaintiff	Mar. 31, 2022USD ($)	Jun. 30, 2021subsidiary	Mar. 31, 2021USD ($)	Mar. 31, 2022USD ($)	Dec. 31, 2021USD ($)	Aug. 31, 2018
Business Acquisition [Line Items]
Goodwill						$ 1,125,828			$ 1,125,828	$ 1,120,320
Decrease from redemptions or purchase of interests									2,800
Payments to acquire businesses, net of cash acquired						0		$ 13,152
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation
Business Acquisition [Line Items]
Number of plaintiffs | plaintiff					780
Additional Paid-In Capital
Business Acquisition [Line Items]
Decrease from redemptions or purchase of interests									5,800
China
Business Acquisition [Line Items]
Number of subsidiaries with non-controlling interest | subsidiary		2					2
Purchase of interest by parent		$ 8,600
Amount of demand note cancelled		$ 800
Percent of consideration transferred on acquisition date		90.00%
Post-closing payment outstanding						200			200
China | China Subsidiaries
Business Acquisition [Line Items]
Ownership percentage by parent		100.00%
China | Subsidiary One
Business Acquisition [Line Items]
Percent of purchase of interest		15.00%					15.00%
China | Subsidiary Two
Business Acquisition [Line Items]
Percent of purchase of interest		33.00%					33.00%
Regulatory Compliance Associates Inc. (RCA)
Business Acquisition [Line Items]
Purchase price	$ 31,000
Cash acquired from acquisition	$ 600
Goodwill						20,700			20,700
Regulatory Compliance Associates Inc. (RCA) | Customer relationships
Business Acquisition [Line Items]
Finite-lived intangibles						$ 12,500			$ 12,500
Nelson Fairfield
Business Acquisition [Line Items]
Purchase price			$ 12,400
Interest acquired			15.00%								85.00%
Step acquisition, gain			$ 1,200
Settlement terms, share value, amount										$ 13,600
BioScience
Business Acquisition [Line Items]
Goodwill				$ 8,400
Payments to acquire businesses, net of cash acquired				13,500
Cash acquired				200
Liabilities incurred				$ 1,900

Inventories (Details)

Inventories (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 32,451	$ 41,514
Work-in-process	758	3,919
Finished goods	12,618	8,979
Inventories, gross	45,827	54,412
Reserve for excess and obsolete inventory	(126)	(124)
Inventories, net	$ 45,701	$ 54,288

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid taxes	$ 26,752	$ 24,937
Prepaid business insurance	8,107	10,707
Prepaid rent	1,203	920
Customer contract assets	18,547	15,565
Insurance and indemnification receivables	3,805	3,144
Current deposits	493	623
Prepaid maintenance contracts	336	279
Value added tax receivable	1,500	2,512
Prepaid software licensing	1,428	2,055
Stock supplies	3,587	3,374
Embedded derivative assets	1,842	496
Other	16,356	7,311
Prepaid expenses and other current assets	$ 83,956	$ 71,923

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Goodwill (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,120,320
Adjustments	56
Changes due to foreign currency exchange rates	5,452
Ending balance	1,125,828
Sterigenics
Goodwill [Roll Forward]
Beginning balance	660,743
Adjustments	0
Changes due to foreign currency exchange rates	1,733
Ending balance	662,476
Nordion
Goodwill [Roll Forward]
Beginning balance	288,905
Adjustments	0
Changes due to foreign currency exchange rates	4,423
Ending balance	293,328
Nelson Labs
Goodwill [Roll Forward]
Beginning balance	170,672
Adjustments	56
Changes due to foreign currency exchange rates	(704)
Ending balance	$ 170,024

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Intangibles (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 1,018,831	$ 1,015,408
Accumulated Amortization	545,844	524,507
Acquired Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	109,157	107,943
Total	1,127,988	1,123,351
Regulatory licenses and other
Acquired Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 83,375	82,110
Renewal term	10 years
Trade names / trademarks
Acquired Indefinite-lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 25,782	25,833
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	668,034	668,628
Accumulated Amortization	380,341	365,935
Proprietary technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	89,037	88,826
Accumulated Amortization	46,268	44,866
Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	170	145
Accumulated Amortization	139	116
Land-use rights
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	9,773	9,744
Accumulated Amortization	1,650	1,586
Sealed source and supply agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	245,334	241,611
Accumulated Amortization	114,818	109,838
Other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	6,483	6,454
Accumulated Amortization	$ 2,628	$ 2,166

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 20,182	$ 22,282
Finite-lived intangible assets, remaining amortization period	9 years 6 months
Other
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 20,200	22,300
Other | Cost of Revenue
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	4,300	5,800
Other | Selling, General and Administrative Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 15,900	$ 16,500

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets - Future Amortization Expense (Details) $ in Thousands	Mar. 31, 2022USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
For the remainder of 2022	$ 62,157
2023	82,016
2024	81,237
2025	43,437
2026	23,181
Thereafter	180,959
Total	$ 472,987

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Accrued employee compensation	$ 29,391	$ 33,334
Legal reserves	3,134	3,259
Accrued interest expense	10,132	10,755
Embedded derivatives	308	0
Professional fees	7,708	4,314
Accrued utilities	1,833	1,797
Insurance accrual	1,407	2,068
Accrued taxes	2,333	2,209
Other	4,213	4,125
Accrued liabilities	$ 60,459	$ 61,861

Long-Term Debt - Schedule of De

Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 1,763,550	$ 1,763,550
Less unamortized debt issuance costs and debt discounts	(19,009)	(20,016)
Long-term Debt	1,763,550
Total long-term debt, less debt issuance costs and debt discounts	1,744,541	1,743,534
Term Loan | Term loan, due 2026
Debt Instrument [Line Items]
Total long-term debt	1,763,100	1,763,100
Other long-term debt
Debt Instrument [Line Items]
Total long-term debt	$ 450	$ 450

Long-Term Debt - Senior Secured

Long-Term Debt - Senior Secured Credit Facilities (Details) - USD ($)	Mar. 26, 2021	Jan. 20, 2021	Jan. 19, 2021	Mar. 31, 2022	Mar. 31, 2021	Dec. 31, 2021	Jul. 31, 2020	Dec. 13, 2019
Debt Instrument [Line Items]
Total long-term debt				$ 1,763,550,000		$ 1,763,550,000
Senior Secured Credit Facilities | Term Loan
Debt Instrument [Line Items]
Debt issuance costs				2,500,000		2,700,000
Debt discount				16,500,000		17,300,000
Term loan, due 2026 | Term Loan
Debt Instrument [Line Items]
Total long-term debt				$ 1,763,100,000		1,763,100,000
Weighted average interest rate				3.25%	3.73%
Effective reduction in current interest rates		2.25%
Term loan, due 2026 | Term Loan | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate		2.75%	4.50%
LIBOR floor		0.50%	1.00%
Write-off of unamortized debt issuance costs and debt discounts		$ 11,300,000
Additional expense		$ 2,900,000
First Lien Notes due 2026 | Secured Debt
Debt Instrument [Line Items]
Weighted average interest rate				7.00%
LIBOR floor							1.00%
First Lien Notes due 2026 | Secured Debt | LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%			6.00%
First Lien Notes due 2026 | Secured Debt | Alternative Base Rate
Debt Instrument [Line Items]
Basis spread on variable rate	1.75%
First Lien Notes due 2026 | Secured Debt | Eurodollar | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	3.50%
First Lien Notes due 2026 | Secured Debt | Eurodollar | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	4.00%
Revolving Credit Facility | Senior Secured Credit Facilities
Debt Instrument [Line Items]
Maximum borrowing capacity								$ 347,500,000
Debt outstanding				$ 0		$ 0
Letters of credit outstanding, amount				69,200,000
Unused borrowing capacity				$ 278,300,000
Revolving Credit Facility | Senior Secured Credit Facilities | Alternative Base Rate | Minimum
Debt Instrument [Line Items]
Basis spread on variable rate	2.50%
Revolving Credit Facility | Senior Secured Credit Facilities | Alternative Base Rate | Maximum
Debt Instrument [Line Items]
Basis spread on variable rate	3.00%

Long-Term Debt - First Lien Not

Long-Term Debt - First Lien Notes (Details) - Secured Debt - First Lien Notes due 2026 - USD ($)	Mar. 26, 2021	Jul. 31, 2020	Mar. 31, 2022
Debt Instrument [Line Items]
Face amount		$ 100,000,000
Redemption premium		3,000,000
Write off of deferred debt issuance cost		$ 3,400,000
LIBOR floor		1.00%
Weighted average interest rate			7.00%
LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%		6.00%

Long-Term Debt - Aggregate Matu

Long-Term Debt - Aggregate Maturities (Details) $ in Thousands	Mar. 31, 2022USD ($)
Debt Disclosure [Abstract]
2022	$ 0
2023	450
2024	0
2025	0
2026	1,763,100
Thereafter	0
Total	$ 1,763,550

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Income Tax Disclosure [Abstract]
Effective income tax rate	32.30%	21.40%

Employee Benefits - Net Periodi

Employee Benefits - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Defined benefit pension plan
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 249	$ 298
Interest cost	1,903	1,613
Expected return on plan assets	(3,704)	(3,557)
Amortization of net actuarial (gain) loss	0	267
Net periodic benefit cost	(1,552)	(1,379)
Other benefits plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	7
Interest cost	65	59
Amortization of net actuarial (gain) loss	(2)	8
Net periodic benefit cost	$ 67	$ 74

Employee Benefits - Additional

Employee Benefits - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Dec. 31, 2021
Postemployment Benefits [Abstract]
Expect funding requirements in each of the next five years	$ 3,100
Defined benefit pension plan
Defined Benefit Plan Disclosure [Line Items]
Letters of credit outstanding, amount	$ 46,100	$ 46,200
Defined benefit pension plan | Maximum
Defined Benefit Plan Disclosure [Line Items]
Solvency payment as percent of market value	15.00%

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	$ 586,096	$ 454,574
Balance	642,130	465,744
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(83,566)	(93,842)
Other comprehensive income (loss) before reclassifications	20,882	(3,595)
Amounts reclassified from accumulated other comprehensive income (loss)	(2)	275
Net current-period other comprehensive income (loss)	20,880	(3,320)
Balance	(62,686)	(97,162)
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(17,581)	(44,143)
Other comprehensive income (loss) before reclassifications	(272)	(524)
Amounts reclassified from accumulated other comprehensive income (loss)	(2)	275
Net current-period other comprehensive income (loss)	(274)	(249)
Balance	(17,855)	(44,392)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	(66,389)	(49,699)
Other comprehensive income (loss) before reclassifications	14,975	(3,071)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Net current-period other comprehensive income (loss)	14,975	(3,071)
Balance	(51,414)	(52,770)
Interest Rate Swaps
Accumulated Other Comprehensive Income (Loss) [Line Items]
Balance	404	0
Other comprehensive income (loss) before reclassifications	6,179	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	0
Net current-period other comprehensive income (loss)	6,179	0
Balance	$ 6,583	$ 0

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
2020 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 3,900	$ 2,800
Restricted Stock | Pre-IPO B-1
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	5 years
Share-based compensation expense	$ 600	700
Restricted Stock | Pre-IPO B-1 | Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	20.00%
Restricted Stock | Pre-IPO B-1 | Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	20.00%
Restricted Stock | Pre-IPO B-1 | Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	20.00%
Restricted Stock | Pre-IPO B-1 | Year Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	20.00%
Restricted Stock | Pre-IPO B-1 | Year Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage	20.00%
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Contractual term	10 years
Stock Options | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	3 years
Stock Options | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
Stock Options | 2020 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 1,500	1,300
RSUs | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	1 year
RSUs | Maximum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting period	4 years
RSUs | 2020 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 2,400	$ 1,500

Share-Based Compensation - Pre-

Share-Based Compensation - Pre-IPO Awards (Class B-1 and B-2) (Details) - Restricted Stock	3 Months Ended
	Mar. 31, 2022shares
Pre-IPO B-1
Number of Shares
Beginning balance (in shares)	1,206,089
Forfeited (in shares)	(15,793)
Vested (in shares)	(144,713)
Ending balance (in shares)	1,045,583
Pre-IPO B-2
Number of Shares
Beginning balance (in shares)	2,023,959
Forfeited (in shares)	(40,616)
Vested (in shares)	0
Ending balance (in shares)	1,983,343

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details)	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Number of Shares
Beginning balance (in shares) | shares	2,423,256
Granted (in shares) | shares	1,401,535
Forfeited (in shares) | shares	(33,586)
Exercised (in shares) | shares	0
Ending balance (in shares) | shares	3,791,205
Weighted- average Exercise Price
Beginning balance (in shares) | $ / shares	$ 23.02
Granted (in dollars per share) | $ / shares	20.03
Forfeited (in dollars per share) | $ / shares	22.97
Exercised (in dollars per share) | $ / shares	0
Ending balance (in shares) | $ / shares	$ 21.92

Share-Based Compensation - RSUs

Share-Based Compensation - RSUs (Details) - RSUs	3 Months Ended
	Mar. 31, 2022$ / sharesshares
Number of Shares
Beginning balance (in shares) | shares	640,122
Granted (in shares) | shares	820,666
Forfeited (in shares) | shares	(18,223)
Vested (in shares) | shares	(2,713)
Ending balance (in shares) | shares	1,439,852
Weighted- average Grant Date Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 23.19
Granted (in dollars per share) | $ / shares	20.65
Forfeited (in dollars per share) | $ / shares	23.04
Vested (in dollars per share) | $ / shares	26.10
Ending balance (in dollars per share) | $ / shares	$ 21.74

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Earnings:
Net income	$ 30,641	$ 11,065
Less: Net income attributable to noncontrolling interests	0	223
Less: Allocation to participating securities	338	157
Less: Allocation to participating securities	338	157
Net income attributable to Sotera Health Company common shareholders	30,303	10,685
Net income attributable to Sotera Health Company common shareholders	$ 30,303	$ 10,685
Weighted Average Common Shares:
Weighted-average common shares outstanding - basic (in shares)	279,829,000	278,827,000
Dilutive effect of potential common shares (in shares)	79,000	141,000
Weighted-average common shares outstanding - diluted (in shares)	279,908,000	278,968,000
Earnings per Common Share:
Net income (loss) attributable to Sotera Health Company common shareholders - basic (in dollars per share)	$ 0.11	$ 0.04
Net income (loss) attributable to Sotera Health Company common shareholders - diluted (in dollars per share)	$ 0.11	$ 0.04
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	3,061,000	2,404,000
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	2,889,000	2,400,000
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	172,000	4,000

Commitments and Contingencies (

Commitments and Contingencies (Details) $ in Millions	Sep. 03, 2021USD ($)	Sep. 03, 2021CAD ($)	Aug. 21, 2020plaintiff	Aug. 17, 2020plaintiff	Mar. 30, 2020USD ($)	Mar. 30, 2020CAD ($)	Oct. 22, 2010USD ($)	Mar. 31, 2022USD ($)	Mar. 31, 2022USD ($)claimsegment
Gain Contingencies [Line Items]
Loss contingency, insurance limits per occurrence								$ 10,000,000
Loss contingency, insurance limits								20,000,000
Nordion v Factory Mutual Insurance Company, 2010 Business Interruption Loss | Positive Outcome of Litigation
Gain Contingencies [Line Items]
Damages sought, value							$ 25,000,000
Period of inability							15 months
Amount awarded from other party, before pre-judgment interest					$ 25,000,000
Amount awarded from other party	$ 500,000	$ 0.6			39,800,000	$ 56.4
Costs assessed and awarded in favor					$ 1,000,000	$ 1.3
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation
Gain Contingencies [Line Items]
Number of plaintiffs | plaintiff			780
Ethylene Oxide Tort Litigation – Georgia | Pending Litigation
Gain Contingencies [Line Items]
Number of plaintiffs | plaintiff				300
Consolidated claims | segment									2
Loss contingency, insurance limits								10,000,000
Loss contingency, utilized limits								$ 5,400,000	$ 5,400,000
Ethylene Oxide Tort Litigation – Georgia | Pending Litigation | Gwinnett County
Gain Contingencies [Line Items]
Consolidated claims | segment									1
Ethylene Oxide Tort Litigation – Georgia | Pending Litigation | Subsidiaries
Gain Contingencies [Line Items]
Number of new claims filed | claim									2
Property Devaluation | Pending Litigation
Gain Contingencies [Line Items]
Consolidated claims | segment									2

Financial Instruments and Fin_3

Financial Instruments and Financial Risk - Additional Information (Details)	3 Months Ended
	Mar. 31, 2022USD ($)	Mar. 31, 2021USD ($)	Dec. 31, 2021USD ($)	Oct. 31, 2021USD ($)instrument	Sep. 30, 2021USD ($)	Feb. 28, 2021USD ($)instrument	Jun. 30, 2020USD ($)instrument
Derivative [Line Items]
Notional amount	$ 2,193,000		$ 2,644,400
Derivative loss, net of tax recognized in accumulated other comprehensive income (loss)	6,179,000	$ 0
Allowance for uncollectible accounts	1,458,000		1,287,000
Foreign Currency Forward Contracts
Derivative [Line Items]
Fair value of outstanding contracts	0		0
Derivatives Designated in Hedge Relationships
Derivative [Line Items]
Derivative loss, net of tax recognized in accumulated other comprehensive income (loss)	3,100,000
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Number of instruments held | instrument				2
Notional amount	1,000,000		1,000,000	$ 1,000,000,000
Option premium				$ 1,800,000
Percent of borrowing limitation due to cash flow exposure				1.00%
Derivatives Not Designated in Hedge Relationships | Interest Rate Swap
Derivative [Line Items]
Notional amount					$ 1,000,000,000
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Number of instruments held | instrument						2
Notional amount	$ 1,000,000		$ 1,500,000			$ 1,000,000,000	$ 1,000,000,000
Option premium						$ 400,000	$ 300,000
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap | LIBOR
Derivative [Line Items]
Variable rate					0.50%	0.50%	1.00%
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap June 2020
Derivative [Line Items]
Number of instruments held | instrument							2
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Notional amount							$ 500,000,000
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap February 2021
Derivative [Line Items]
Number of instruments amended | instrument						2

Financial Instruments and Fin_4

Financial Instruments and Financial Risk - Derivative Instruments (Details) - USD ($)	Mar. 31, 2022	Dec. 31, 2021	Oct. 31, 2021	Feb. 28, 2021	Jun. 30, 2020
Derivative [Line Items]
Notional Amount	$ 2,193,000	$ 2,644,400
Fair Value, Derivative Asset	20,452,000	4,472,000
Fair Value, Derivative Liabilities	308,000	0
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Notional Amount	1,000,000	1,000,000	$ 1,000,000,000
Fair Value, Derivative Asset	10,610,000	2,322,000
Fair Value, Derivative Liabilities	0	0
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Notional Amount	1,000,000	1,500,000		$ 1,000,000,000	$ 1,000,000,000
Fair Value, Derivative Asset	8,000,000	1,654,000
Fair Value, Derivative Liabilities	0	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative
Derivative [Line Items]
Notional Amount	193,000	144,400
Fair Value, Derivative Asset	1,842,000	496,000
Fair Value, Derivative Liabilities	$ 308,000	$ 0

Financial Instruments and Fin_5

Financial Instruments and Financial Risk - Activities of Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Interest Rate Cap | Interest Expense, Net
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized loss (gain)	$ (6,346)	$ 90
Embedded Derivative | Other Income, Net
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized loss (gain)	(1,018)	(853)
Foreign Currency Forward Contracts | Foreign Exchange (Gain) Loss
Derivative Instruments, Gain (Loss) [Line Items]
Realized loss	$ (1,530)	$ (2,374)

Financial Instruments and Fin_6

Financial Instruments and Financial Risk - Reclassification from Accumulated Other Comprehensive Income (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Unrealized gain (loss) on interest rate derivatives recorded in other comprehensive income	$ 6,179	$ 0

Financial Instruments and Fin_7

Financial Instruments and Financial Risk - Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Derivative [Line Items]
Derivative asset	$ 20,452	$ 4,472
Derivative liabilities	(308)	0
Derivatives Not Designated in Hedge Relationships | Term loan, due 2026 | Fair Value, Level 1
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Term loan, due 2026 | Fair Value, Level 2
Derivative [Line Items]
Long-term debt	1,744,411	1,754,285
Derivatives Not Designated in Hedge Relationships | Term loan, due 2026 | Fair Value, Level 3
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Other long-term debt | Fair Value, Level 1
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Other long-term debt | Fair Value, Level 2
Derivative [Line Items]
Long-term debt	445	444
Derivatives Not Designated in Hedge Relationships | Other long-term debt | Fair Value, Level 3
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Finance Lease Obligations (with current portion) | Fair Value, Level 1
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Finance Lease Obligations (with current portion) | Fair Value, Level 2
Derivative [Line Items]
Long-term debt	41,356	42,037
Derivatives Not Designated in Hedge Relationships | Finance Lease Obligations (with current portion) | Fair Value, Level 3
Derivative [Line Items]
Long-term debt	0	0
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Derivative asset	8,000	1,654
Derivative liabilities	0	0
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 1
Derivative [Line Items]
Derivative asset	0	0
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 2
Derivative [Line Items]
Derivative asset	8,000	1,654
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 3
Derivative [Line Items]
Derivative asset	0	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative
Derivative [Line Items]
Derivative asset	1,842	496
Derivative liabilities	(308)	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 1
Derivative [Line Items]
Derivative asset	0	0
Derivative liabilities	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 2
Derivative [Line Items]
Derivative asset	1,842	496
Derivative liabilities	308
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 3
Derivative [Line Items]
Derivative asset	0	0
Derivative liabilities	0
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Term loan, due 2026
Derivative [Line Items]
Long-term debt	1,744,096	1,743,090
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Other long-term debt
Derivative [Line Items]
Long-term debt	445	444
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Finance Lease Obligations (with current portion)
Derivative [Line Items]
Long-term debt	41,356	42,037
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Interest Rate Cap
Derivative [Line Items]
Derivative asset	8,000	1,654
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Embedded Derivative
Derivative [Line Items]
Derivative asset	1,842	496
Derivative liabilities	308
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Derivative asset	10,610	2,322
Derivative liabilities	0	0
Derivatives Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 1
Derivative [Line Items]
Derivative asset	0	0
Derivatives Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 2
Derivative [Line Items]
Derivative asset	10,610	2,322
Derivatives Designated in Hedge Relationships | Interest Rate Cap | Fair Value, Level 3
Derivative [Line Items]
Derivative asset	0	0
Derivatives Designated in Hedge Relationships | Carrying Amount | Interest Rate Cap
Derivative [Line Items]
Derivative asset	$ 10,610	$ 2,322

Segment Information - Additiona

Segment Information - Additional Information (Details) - segment	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting [Abstract]
Number of operating segments	3
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer One
Segment Reporting Information [Line Items]
Percentage	15.70%	23.70%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Two
Segment Reporting Information [Line Items]
Percentage	14.40%	20.00%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Three
Segment Reporting Information [Line Items]
Percentage	13.90%	12.20%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Four
Segment Reporting Information [Line Items]
Percentage	12.20%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Five
Segment Reporting Information [Line Items]
Percentage	11.90%

Segment Information - Segment O

Segment Information - Segment Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Net revenues	$ 236,754	$ 212,148
Sterigenics
Segment Reporting Information [Line Items]
Net revenues	149,462	131,151
Nordion
Segment Reporting Information [Line Items]
Net revenues	34,002	25,918
Nelson Labs
Segment Reporting Information [Line Items]
Net revenues	53,290	55,079
Operating Segments
Segment Reporting Information [Line Items]
Net revenues	236,754	212,148
Segment income	115,349	105,317
Total capital expenditures	35,546	20,942
Operating Segments | Sterigenics
Segment Reporting Information [Line Items]
Net revenues	149,462	131,151
Segment income	79,403	68,461
Total capital expenditures	25,221	19,514
Operating Segments | Nordion
Segment Reporting Information [Line Items]
Net revenues	34,002	25,918
Segment income	18,903	13,786
Total capital expenditures	7,090	489
Operating Segments | Nelson Labs
Segment Reporting Information [Line Items]
Net revenues	53,290	55,079
Segment income	17,043	23,070
Total capital expenditures	3,235	939
Intersegment
Segment Reporting Information [Line Items]
Net revenues	$ (15,500)	$ (10,500)

Segment Information - Reconcili

Segment Information - Reconciliation of Reportable Segment Amounts (Details) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2022	Mar. 31, 2021
Segment Reporting Information [Line Items]
Share-based compensation expense	$ 4,538	$ 3,449
Loss on extinguishment of debt	0	14,312
Accretion of asset retirement obligations	520	551
Net income attributable to Sotera Health Company	30,641	10,842
Interest Rate Swap | Derivatives Not Designated in Hedge Relationships
Segment Reporting Information [Line Items]
Unrealized gain	6,300
Operating Segments
Segment Reporting Information [Line Items]
Segment income	115,349	105,317
Segment Reconciling Items
Segment Reporting Information [Line Items]
Interest expense, net	16,750	21,282
Depreciation and amortization	36,049	37,661
Share-based compensation expense	4,538	3,449
(Gain) loss on foreign currency and embedded derivatives	(6,552)	(336)
Acquisition and divestiture related charges, net	(160)	(185)
Business optimization project expenses	104	261
Plant closure expenses	671	542
Loss on extinguishment of debt	0	14,312
Professional services relating to EO sterilization facilities	18,059	13,399
Accretion of asset retirement obligations	520	551
COVID-19 expenses	103	299
Net income attributable to Sotera Health Company	$ 45,267	$ 14,082