Sotera Health (SHC) 10-Q 2 Nov 22 2022 Q3 Quarterly report Financial data

Cover

Cover - shares	9 Months Ended
	Sep. 30, 2022	Oct. 25, 2022
Cover [Abstract]
Document Type	10-Q
Document Quarterly Report	true
Document Period End Date	Sep. 30, 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		282,113,499
Entity Central Index Key	0001822479
Current Fiscal Year End Date	--12-31
Amendment Flag	false
Document Fiscal Year Focus	2022
Document Fiscal Period Focus	Q3

Consolidated Balance Sheets

Consolidated Balance Sheets - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Current assets:
Cash and cash equivalents	$ 163,975	$ 106,917
Restricted cash short-term	986	7
Accounts receivable, net of allowance for uncollectible accounts of $1,414 and $1,287, respectively	111,613	108,183
Inventories, net	37,153	54,288
Prepaid expenses and other current assets	81,673	71,923
Income taxes receivable	25,334	4,643
Total current assets	420,734	345,961
Property, plant, and equipment, net	704,406	650,797
Operating lease assets	27,194	39,946
Deferred income taxes	5,087	5,885
Investment in unconsolidated affiliate	0	9,405
Post-retirement assets	9,856	5,478
Other assets	47,131	12,866
Other intangible assets, net	503,755	598,844
Goodwill	1,092,469	1,120,320
Total assets	2,810,632	2,789,502
Current liabilities:
Accounts payable	60,730	72,868
Accrued liabilities	56,762	61,861
Deferred revenue	5,347	8,669
Current portion of finance lease obligations	1,591	1,160
Current portion of operating lease obligations	7,718	9,289
Current portion of asset retirement obligations	532	619
Income taxes payable	7,351	6,695
Total current liabilities	140,031	161,161
Long-term debt	1,746,555	1,743,534
Finance lease obligations, less current portion	54,935	40,877
Operating lease obligations, less current portion	22,174	33,017
Noncurrent asset retirement obligations	43,889	41,833
Deferred lease income	18,769	20,745
Post-retirement obligations	10,485	11,464
Noncurrent liabilities	15,345	16,274
Deferred income taxes	151,720	134,501
Total liabilities	2,203,903	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 September 30, 2022 and December 31, 2021, respectively	2,860	2,860
Preferred stock, with $0.01 par value, 120,000 authorized no shares issued at September 30, 2022 and December 31, 2021, respectively	0	0
Treasury stock, at cost (3,924 and 3,052 shares at September 30, 2022 and December 31, 2021, respectively)	(32,653)	(33,545)
Additional paid-in capital	1,186,620	1,172,593
Retained deficit	(386,097)	(472,246)
Accumulated other comprehensive loss	(164,001)	(83,566)
Total equity attributable to Sotera Health Company	606,729	586,096
Noncontrolling interests	0	0
Total equity	606,729	586,096
Total liabilities and equity	$ 2,810,632	$ 2,789,502

Consolidated Balance Sheets (Pa

Consolidated Balance Sheets (Parenthetical) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Statement of Financial Position [Abstract]
Allowance for uncollectible accounts	$ 1,414	$ 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)	3,924,000	3,052,000

Consolidated Statements of Oper

Consolidated Statements of Operations and Comprehensive Income (Loss) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Revenues:
Total net revenues	$ 248,704	$ 226,164	$ 752,097	$ 690,229
Cost of revenues:
Total cost of revenues	112,691	100,578	336,813	305,510
Gross profit	136,013	125,586	415,284	384,719
Operating expenses:
Selling, general and administrative expenses	57,091	44,038	179,765	146,331
Amortization of intangible assets	15,727	15,877	47,337	48,081
Total operating expenses	72,818	59,915	227,102	194,412
Operating income	63,195	65,671	188,182	190,307
Interest expense, net	23,427	18,140	47,875	58,585
Impairment of investment in unconsolidated affiliate	0	0	9,613	0
Loss on extinguishment of debt	0	6,365	0	20,677
Foreign exchange (gain) loss	(535)	756	(502)	1,410
Other income, net	(1,713)	(693)	(4,195)	(7,347)
Income before income taxes	42,016	41,103	135,391	116,982
Provision for income taxes	16,926	13,659	49,242	35,858
Net income	25,090	27,444	86,149	81,124
Less: Net income attributable to noncontrolling interests	0	0	0	239
Net income attributable to Sotera Health Company	25,090	27,444	86,149	80,885
Other comprehensive income (loss) net of tax:
Pension and post-retirement benefits (net of taxes of $357, $466, $444, and $240, respectively)	1,065	1,383	1,323	713
Interest rate derivatives (net of taxes of $3,368, $—, $6,718 and $—, respectively)	9,408	0	18,765	0
Foreign currency translation	(69,460)	(29,867)	(100,523)	(12,528)
Comprehensive income (loss)	(33,897)	(1,040)	5,714	69,309
Less: comprehensive income attributable to noncontrolling interests	0	0	0	534
Comprehensive income (loss) attributable to Sotera Health Company	$ (33,897)	$ (1,040)	$ 5,714	$ 68,775
Earnings per share:
Basic (in dollars per share)	$ 0.09	$ 0.10	$ 0.31	$ 0.29
Diluted (in dollars per share)	$ 0.09	$ 0.10	$ 0.31	$ 0.29
Weighted average number of shares outstanding:
Basic (in shares)	280,142	279,381	279,988	279,097
Diluted (in shares)	280,172	279,560	280,093	279,253
Service
Revenues:
Total net revenues	$ 216,704	$ 200,499	$ 644,451	$ 597,907
Cost of revenues:
Total cost of revenues	99,772	88,349	292,755	264,776
Product
Revenues:
Total net revenues	32,000	25,665	107,646	92,322
Cost of revenues:
Total cost of revenues	$ 12,919	$ 12,229	$ 44,058	$ 40,734

Consolidated Statements of Op_2

Consolidated Statements of Operations and Comprehensive Income (Loss) (Parenthetical) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Statement [Abstract]
Pension and post-retirement benefits, tax	$ 357	$ 466	$ 444	$ 240
Interest rate swaps, tax	$ 3,368	$ 0	$ 6,718	$ 0

Consolidated Statements of Cash

Consolidated Statements of Cash Flows - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021
Operating activities:
Net income	$ 86,149	$ 81,124
Adjustments to reconcile net income to net cash provided by operating activities:
Depreciation	47,496	47,457
Amortization of intangible assets	61,596	65,299
Impairment of investment in unconsolidated affiliate	9,613	0
Loss on extinguishment of debt	0	20,677
Deferred income taxes	17,153	8,131
Share-based compensation expense	14,955	10,489
Accretion of asset retirement obligations	1,645	1,751
Unrealized foreign exchange (gain) loss	(5,610)	715
Unrealized gain on derivatives not designated as hedging instruments	(4,323)	(424)
Amortization of debt issuance costs	4,259	4,789
Other	(6,109)	(6,174)
Changes in operating assets and liabilities:
Accounts receivable	(8,558)	(4,901)
Inventories	13,896	(3,429)
Other current assets	(13,066)	2,225
Accounts payable	(13,367)	(291)
Accrued liabilities	(1,874)	(7,985)
Income taxes payable / receivable, net	(25,050)	(3,620)
Other liabilities	1,489	(290)
Other long-term assets	(4,259)	(349)
Net cash provided by operating activities	176,035	215,194
Investing activities:
Purchases of property, plant and equipment	(110,642)	(60,898)
Purchase of mandatorily redeemable noncontrolling interest in Nelson Laboratories Fairfield, Inc.	0	(12,425)
Purchase of BioScience Laboratories, LLC, net of cash acquired	0	(13,530)
Adjustment to purchase of Regulatory Compliance Associates Inc.	450	0
Other investing activities	34	(717)
Net cash used in investing activities	(110,158)	(87,570)
Financing activities:
Purchase of noncontrolling interests in China subsidiaries	0	(8,418)
Payments of debt issuance costs and prepayment premium	(31)	(6,718)
Payments on debt	0	(100,000)
Other financing activities	(1,452)	(368)
Net cash used in financing activities	(1,483)	(115,504)
Effect of exchange rate changes on cash and cash equivalents	(6,357)	345
Net increase in cash and cash equivalents, including restricted cash	58,037	12,465
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	164,961	114,919
Supplemental disclosures of cash flow information:
Cash paid during the period for interest	65,045	53,726
Cash paid during the period for income taxes, net of tax refunds received	56,474	31,922
Purchases of property, plant and equipment included in accounts payable	$ 18,583	$ 14,527

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
Beginning balance at Dec. 31, 2020	$ 454,574	$ 2,860		$ 1,166,412	$ (589,128)	$ (93,842)	$ 2,272
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Acquisition of noncontrolling interests	(8,578)			(5,772)			(2,806)
Issuance of shares (in shares)		47
Issuance of shares	$ 1,080			1,080
Share-based compensation plans (in shares)	(378)
Share-based compensation plans	$ 9,384			9,384
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	713					713
Foreign currency translation	(12,528)					(12,823)	295
Interest rate derivatives, net of tax	0
Net income	81,124				80,885		239
Balance (in shares) at Sep. 30, 2021		282,917
Ending balance at Sep. 30, 2021	525,769	$ 2,860		1,171,104	(508,243)	(105,952)	0
Balance (in shares) at Jun. 30, 2021		282,917
Beginning balance at Jun. 30, 2021	523,271	$ 2,860		1,167,566	(535,687)	(77,468)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation plans	3,538			3,538
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	1,383					1,383
Foreign currency translation	(29,867)					(29,867)
Interest rate derivatives, net of tax	0
Net income	27,444				27,444
Balance (in shares) at Sep. 30, 2021		282,917
Ending balance at Sep. 30, 2021	525,769	$ 2,860		1,171,104	(508,243)	(105,952)	0
Balance (in shares) at Dec. 31, 2021		282,985
Beginning 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)		(872)
Share-based compensation plans	14,919		892	14,027
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	1,323					1,323
Foreign currency translation	(100,523)					(100,523)
Interest rate derivatives, net of tax	18,765					18,765
Net income	86,149				86,149
Balance (in shares) at Sep. 30, 2022		282,113
Ending balance at Sep. 30, 2022	606,729	$ 2,860	(32,653)	1,186,620	(386,097)	(164,001)	0
Balance (in shares) at Jun. 30, 2022		282,902
Beginning balance at Jun. 30, 2022	636,000	$ 2,860	(32,654)	1,181,995	(411,187)	(105,014)	0
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation plans (in shares)		(789)
Share-based compensation plans	4,626		1	4,625
Comprehensive income (loss):
Pension and post-retirement plan adjustments, net of tax	1,065					1,065
Foreign currency translation	(69,460)					(69,460)
Interest rate derivatives, net of tax	9,408					9,408
Net income	25,090				25,090
Balance (in shares) at Sep. 30, 2022		282,113
Ending balance at Sep. 30, 2022	$ 606,729	$ 2,860	$ (32,653)	$ 1,186,620	$ (386,097)	$ (164,001)	$ 0

Basis of Presentation

Basis of Presentation	9 Months Ended
	Sep. 30, 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 leading global provider of mission-critical end-to-end sterilization solutions, lab testing and advisory services for the healthcare industry 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 represent 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% of 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 interest on our Consolidated Statements of Operations and Comprehensive Income (Loss) 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 Auralux Enterprises, Ltd (“Auralux”) 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 concluded that we are not the primary beneficiary of the VIE. This investment is accounted for using the equity method. The investment is reflected within “Investment in unconsolidated affiliates” on the Consolidated Balance Sheets. During the three months ended June 30, 2022, we identified certain events and circumstances that indicated a decline in value of our investment in this joint venture that was other-than-temporary. Consequently, as of June 30, 2022, we wrote down the investment in the joint venture to its fair value of $0, resulting in an impairment charge of approximately $9.6 million. 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	9 Months Ended
	Sep. 30, 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. ASUs 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	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2022 and 2021: (thousands of U.S. dollars) Three Months Ended September 30, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 157,723 $ 33,830 $ — $ 191,553 Over time — 1,241 55,910 57,151 Total $ 157,723 $ 35,071 $ 55,910 $ 248,704 (thousands of U.S. dollars) Three Months Ended September 30, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 145,314 $ 28,768 $ — $ 174,082 Over time — — 52,082 52,082 Total $ 145,314 $ 28,768 $ 52,082 $ 226,164 (thousands of U.S. dollars) Nine Months Ended September 30, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 464,977 $ 113,501 $ — $ 578,478 Over time — 6,050 167,569 173,619 Total $ 464,977 $ 119,551 $ 167,569 $ 752,097 (thousands of U.S. dollars) Nine Months Ended September 30, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 421,647 $ 102,439 $ — $ 524,086 Over time — 1,372 164,771 166,143 Total $ 421,647 $ 103,811 $ 164,771 $ 690,229 Contract Balances As of September 30, 2022, and December 31, 2021, contract assets included in “Prepaid expenses and other current assets” on the Consolidated Balance Sheets totaled approximately $22.4 million and $15.6 million, respectively, resulting from revenue recognized over time in excess of the amount billed to the customer.

Acquisitions

Acquisitions	9 Months Ended
	Sep. 30, 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 $30.6 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 expands and further strengthens our technical consulting and expert advisory capabilities within 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. As of September 30, 2022, approximately $25.3 million of goodwill was recorded related to the RCA acquisition, representing the excess of the purchase price over the estimated fair values of all the assets acquired and liabilities assumed. We also recorded $6.4 million of finite-lived intangible assets, primarily related to customer relationships. 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 September 30, 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 (Loss) relative to the $13.6 million previously accrued. Pursuant to the terms of the 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. Approximately $8.4 million of goodwill was recorded related to the BioScience Labs acquisition, representing the excess of the purchase price over the 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 the Company's consolidated financial statements.

Inventories

Inventories	9 Months Ended
	Sep. 30, 2022
Inventory Disclosure [Abstract]
Inventories	Inventories Inventories consisted primarily of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Raw materials and supplies $ 31,449 $ 41,514 Work-in-process 389 3,919 Finished goods 5,429 8,979 37,267 54,412 Reserve for excess and obsolete inventory (114) (124) Inventories, net $ 37,153 $ 54,288

Prepaid Expenses and Other Curr

Prepaid Expenses and Other Current Assets	9 Months Ended
	Sep. 30, 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 primarily of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Prepaid taxes $ 29,735 $ 24,937 Prepaid business insurance 1,871 10,707 Prepaid rent 1,111 920 Customer contract assets 22,387 15,565 Insurance and indemnification receivables 4,361 3,144 Current deposits 760 623 Prepaid maintenance contracts 385 279 Value added tax receivable 759 2,512 Prepaid software licensing 2,055 2,055 Stock supplies 3,597 3,374 Embedded derivatives 3,522 496 Other 11,130 7,311 Prepaid expenses and other current assets $ 81,673 $ 71,923

Goodwill and Other Intangible A

Goodwill and Other Intangible Assets	9 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Goodwill and Other Intangible Assets	Goodwill and Other Intangible Assets Changes to goodwill during the nine months ended September 30, 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 — — 4,645 4,645 Changes due to foreign currency exchange rates (5,982) (21,748) (4,766) (32,496) Goodwill at September 30, 2022 $ 654,761 $ 267,157 $ 170,551 $ 1,092,469 Other intangible assets consisted of the following: (thousands of U.S. dollars) Gross Carrying Amount Accumulated Amortization As of September 30, 2022 Finite-lived intangible assets Customer relationships $ 644,236 $ 402,253 Proprietary technology 84,392 48,446 Trade names 2,550 574 Land-use rights 8,715 1,579 Sealed source and supply agreements 201,496 88,712 Other 4,439 1,746 Total finite-lived intangible assets 945,828 543,310 Indefinite-lived intangible assets Regulatory licenses and other (a) 75,888 — Trade names / trademarks 25,349 — Total indefinite-lived intangible assets 101,237 — Total $ 1,047,065 $ 543,310 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. Fully amortized amounts are written off. Amortization expense for other intangible assets was $20.2 million ($4.5 million is included in “Cost of revenues” and $15.7 million in “Selling, general and administrative expenses”) and $61.6 million ($14.3 million is included in “Cost of revenues” and $47.3 million in “Selling, general and administrative expenses”) in the Consolidated Statements of Operations and Comprehensive Income (Loss) for the three and nine months ended September 30, 2022, respectively. Amortization expense for other intangible assets was $21.2 million ($5.3 million is included in “Cost of revenues” and $15.9 million in “Selling, general and administrative expenses”) and $65.3 million ($17.2 million is included in “Cost of revenues” and $48.1 million in “Selling, general and administrative expenses”) in the Consolidated Statements of Operations and Comprehensive Income (Loss) for the three and nine months ended September 30, 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 $ 19,779 2023 79,485 2024 78,709 2025 41,907 2026 21,872 Thereafter 160,766 Total $ 402,518 The weighted-average remaining useful life of the finite-lived intangible assets was approximately 8.5 years as of September 30, 2022.

Accrued Liabilities

Accrued Liabilities	9 Months Ended
	Sep. 30, 2022
Payables and Accruals [Abstract]
Accrued Liabilities	Accrued Liabilities Accrued liabilities consisted of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Accrued employee compensation $ 28,589 $ 33,334 Legal reserves 3,267 3,259 Accrued interest expense 993 10,755 Embedded derivatives 4,745 — Professional fees 8,196 4,314 Accrued utilities 1,885 1,797 Insurance accrual 2,220 2,068 Accrued taxes 3,196 2,209 Other 3,671 4,125 Accrued liabilities $ 56,762 $ 61,861

Long-Term Debt

Long-Term Debt	9 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Long-Term Debt	Long-Term Debt Long-term debt consisted of the following: (thousands of U.S. dollars) September 30, 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 current portion — — Less unamortized debt issuance costs and debt discounts (16,995) (20,016) Total long-term debt, less debt issuance costs and debt discounts $ 1,746,555 $ 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 September 30, 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 September 30, 2022 and September 30, 2021 was 4.96% and 3.25%, respectively, and 3.92% and 3.51% for the nine months ended September 30, 2022 and September 30, 2021, respectively. On January 20, 2 021, 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 resulted 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 (Loss). 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 does 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 September 30, 2022 and December 31, 2021, capitalized debt issuance costs totaled $2.3 million and $2.7 million, respectively, and debt discounts totaled $14.7 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. An event of default under the Senior Secured Credit Facilities would occur if the Company or certain of its subsidiaries received one or more enforceable judgments for payment in an aggregate amount in excess of $100.0 million, which judgment or judgments are not stayed or remain undischarged for a period of sixty 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 September 30, 2022, the Company had $67.6 million of letters of credit issued against the Revolving Credit Facility, resulting in total availability under the Revolving Credit Facility of $279.9 million. Term Loan Interest Rate Risk Management The Company utilizes interest rate derivatives to reduce 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 (Loss) for the three and nine months ended September 30, 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 September 30, 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	9 Months Ended
	Sep. 30, 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 rates were 40.3 % and 36.4% for the three and nine months ended September 30, 2022, respectively, compared to 33.2% and 30.7% for the three and nine months ended September 30, 2021, respectively. Income tax expense for the three months ended September 30, 2022 differed from the statutory rate primarily due to a net increase in the valuation allowance, the impact of the foreign rate differential, and global intangible low-tax income (“GILTI”). The increase in the valuation allowance was attributable to the limitation on the deductibility of interest expense and the impairment of an investment in a joint venture. Income tax expense for the three months ended September 30, 2021 differed from the statutory rate primarily due to the impact of the foreign rate differential, GILTI and a net increase in the interest expense valuation allowance.

Employee Benefits

Employee Benefits	9 Months Ended
	Sep. 30, 2022
Postemployment Benefits [Abstract]
Employee Benefits	Employee BenefitsThe 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 plans The interest cost, expected return on plan assets and amortization of net actuarial loss are recorded 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 (Loss). The components of net periodic pension cost for the defined benefit plans for the three and nine months ended September 30, 2022 and 2021 were as follows: Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Service cost $ 242 $ 300 $ 738 $ 905 Interest cost 1,848 1,622 5,640 4,897 Expected return on plan assets (3,595) (3,577) (10,975) (10,799) Amortization of net actuarial loss — 269 — 811 Net periodic benefit $ (1,505) $ (1,386) $ (4,597) $ (4,186) Other benefit plans Other benefit plans 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 and nine months ended September 30, 2022 and 2021 were as follows: Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Service cost $ 4 $ 7 $ 12 $ 21 Interest cost 63 59 193 179 Amortization of net actuarial loss (gain) (2) 9 (6) 26 Net periodic benefit cost $ 65 $ 75 $ 199 $ 226 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 require solvency testing on defined benefit pension plans.

Related Parties

Related Parties	9 Months Ended
	Sep. 30, 2022
Related Party Transactions [Abstract]
Related Parties	Related PartiesWe do business with a number of companies affiliated with Warburg Pincus and GTCR, which we refer to collectively as the “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)	9 Months Ended
	Sep. 30, 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 Derivatives Total Beginning balance – July 1, 2022 $ (17,323) $ (97,452) $ 9,761 $ (105,014) Other comprehensive income (loss) before reclassifications 1,067 (69,460) 9,408 (58,985) Amounts reclassified from accumulated other comprehensive income (loss) (2) (a) — — (2) Net current-period other comprehensive income (loss) 1,065 (69,460) 9,408 (58,987) Ending balance – September 30, 2022 $ (16,258) $ (166,912) $ 19,169 $ (164,001) Beginning balance – January 1, 2022 $ (17,581) $ (66,389) $ 404 $ (83,566) Other comprehensive income (loss) before reclassifications 1,329 (100,523) 18,765 (80,429) Amounts reclassified from accumulated other comprehensive income (loss) (6) (a) — — (6) Net current-period other comprehensive income (loss) 1,323 (100,523) 18,765 (80,435) Ending balance – September 30, 2022 $ (16,258) $ (166,912) $ 19,169 $ (164,001) (thousands of U.S. dollars) Defined Benefit Plans Foreign Currency Translation Interest Rate Derivatives Total Beginning balance – July 1, 2021 $ (44,813) $ (32,655) $ — $ (77,468) Other comprehensive income (loss) before reclassifications 1,105 (29,867) — (28,762) Amounts reclassified from accumulated other comprehensive income (loss) 278 (a) — — 278 Net current-period other comprehensive income (loss) 1,383 (29,867) — (28,484) Ending balance – September 30, 2021 $ (43,430) $ (62,522) $ — $ (105,952) Beginning balance – January 1, 2021 $ (44,143) $ (49,699) $ — $ (93,842) Other comprehensive income (loss) before reclassifications (124) (12,823) — (12,947) Amounts reclassified from accumulated other comprehensive income (loss) 837 (a) — — 837 Net current-period other comprehensive income (loss) 713 (12,823) — (12,110) Ending balance – September 30, 2021 $ (43,430) $ (62,522) $ — $ (105,952) (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 (Loss).

Share-Based Compensation

Share-Based Compensation	9 Months Ended
	Sep. 30, 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 a five-year vesting period (20% per year) beginning on the original vesting commencement date of the corresponding Class B-1 time vesting units, subject to the grantee’s continued services through each vesting date. Upon the occurrence of a change in control of the Company, all then outstanding unvested shares of our common stock distributed in respect of Class B-1 Units will become vested as of the date of consummation of such change in control, subject to the grantee’s continued services through the consummation of the change in control. 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 September 30, 2022, these awards remain unvested. We recognized $0.5 million and $0.7 million of share-based compensation expense related to the pre-IPO Class B-1 awards for the three months ended September 30, 2022 and 2021, and $1.6 million and $2.0 million for the nine months ended September 30, 2022 and 2021, respectively. A summary of the activity for the nine months ended September 30, 2022 related to the restricted stock awards distributed to 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 (32,614) (925,544) Vested (345,926) — Unvested at September 30, 2022 827,549 1,098,415 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 recognized $4.1 million ($1.5 million for stock options and $2.6 million for RSUs) and $2.9 million ($1.3 million for stock options and $1.6 million for RSUs) of share-based compensation expense for these awards for the three months ended September 30, 2022 and 2021, respectively. We recognized $13.3 million ($5.2 million for stock options and $8.1 million for RSUs) and $8.5 million ($3.9 million for stock options and $4.6 million for RSUs) for the nine months ended September 30, 2022 and 2021, respectively in our Consolidated Statements of Operations and Comprehensive Income (Loss), in “Selling, general and administrative expenses.” Stock Options Stock options generally vest ratably over a period of three Number of Shares Weighted Average Exercise Price At December 31, 2021 2,423,256 $ 23.02 Granted 1,445,887 19.96 Forfeited (454,953) 22.08 Exercised — — At September 30, 2022 3,414,190 $ 21.85 As of September 30, 2022, there were 0.5 million stock options vested or exercisable. 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 954,685 20.57 Forfeited (145,656) 21.90 Vested (89,121) 24.13 Unvested at September 30, 2022 1,360,030 $ 21.43

Earnings Per Share

Earnings Per Share	9 Months Ended
	Sep. 30, 2022
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 Nine Months Ended in thousands of U.S. dollars and share amounts (except per share amounts) September 30, September 30, September 30, September 30, Earnings: Net income $ 25,090 $ 27,444 $ 86,149 $ 81,124 Less: Net income attributable to noncontrolling interests — — — 239 Less: Allocation to participating securities 223 343 862 1,089 Net income attributable to Sotera Health Company common shareholders $ 24,867 $ 27,101 $ 85,287 $ 79,796 Weighted Average Common Shares: Weighted-average common shares outstanding - basic 280,142 279,381 279,988 279,097 Dilutive effect of potential common shares 30 179 105 156 Weighted-average common shares outstanding - diluted 280,172 279,560 280,093 279,253 Earnings per Common Share: Net income per common share attributable to Sotera Health Company common shareholders - basic $ 0.09 $ 0.10 $ 0.31 $ 0.29 Net income per common share attributable to Sotera Health Company common shareholders - diluted 0.09 0.10 0.31 0.29 Diluted earnings per share does not consider the following potential common shares as the effect would be anti-dilutive: Three Months Ended Nine Months Ended in thousands of share amounts September 30, September 30, September 30, September 30, Stock options 3,526 2,403 3,399 2,399 RSUs 1,121 5 34 7 Total anti-dilutive securities 4,647 2,408 3,433 2,406

Commitments and Contingencies

Commitments and Contingencies	9 Months Ended
	Sep. 30, 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 as of September 30, 2022. If a potentially material loss contingency is not probable, but is reasonably possible, or is probable but cannot be estimated, then the nature of the contingent liability, together with an estimate of the range of possible loss if determinable and material, would be disclosed. 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, a potential liability ultimately determined to be attributable to the Company may result in a material impact on the Company’s results of operations, liquidity or financial condition for the annual or interim period during which such liability is accrued. The Company may also incur material defense and settlement costs, diversion of management resources and other adverse effects on our business, financial condition, or results of operations. 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 830 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 are expected to seek compensatory and punitive damages, as permitted by law, in their individual trials. Fact discovery in the Consolidated Case concluded on February 1, 2022. On June 28, 2022 the Court granted summary judgment, dismissing plaintiffs’ ultrahazardous activity / strict liability claims and denying the remainder of the motions. Two of the individual cases included in the Consolidated Case are scheduled for trials in 2022, and two are scheduled for trials in 2023. Plaintiffs in those four cases have been granted permission to seek punitive damage awards against subsidiaries of the Company and another party. The first trial began on August 12, 2022, and on September 19, 2022, the jury rendered a verdict in favor of the plaintiff and awarded damages in the amount of $358.7 million, including $36.1 million of compensatory damages, $320.0 million of punitive damages and $2.6 million of prejudgment interest against our subsidiaries Sterigenics U.S., LLC and Sotera Health LLC. Post-judgment interest accrues on the compensatory and punitive damages awards from September 20, 2022, the date the court entered the judgment order. The Company does not believe that the facts and law justify the verdict or damage awards and intends to vigorously challenge them through all appropriate motions for post-trial relief and appeals. The Company expects the enforceability of the judgment order to be stayed pending the resolution of motions for post-trial relief. In order to stay the enforceability of the judgment order during the appeals process under Illinois law, an appellate bond must be posted or an alternative form of security must be provided. Our subsidiaries are exploring options to post the appellate bond or to provide an alternative form of security, which could involve additional credit support from the Company, if the Company so determines, and/or posting cash collateral of the subsidiaries, or other form of security as may be required by the courts, and on which such subsidiaries will incur interest and other associated costs. The bond or other form of security ordinarily must be sufficient to cover the amount of the judgment and costs, plus interest reasonably anticipated to accrue during pendency of the appeal. Given the pendency of motions for post-trial relief requesting that the trial court enter judgment in defendants’ favor notwithstanding the verdict, or alternatively that a new trial be granted, or alternatively for reduction of the compensatory and punitive damages awards, as well as the courts’ ability to reduce the amount of any bond or other security, the amount of the bond or alternative form of security that will ultimately be required to be posted or provided is uncertain. On October 26, 2022, Sterigenics U.S., LLC and Sotera Health LLC filed their motion for post-trial relief, requesting that the trial court enter judgment in their favor notwithstanding the verdict, or alternatively that a new trial be granted, and requesting reduction of the compensatory and punitive damages awards, based on the plaintiff’s failure of proof on elements of her claims, reversible errors by the trial court regarding evidentiary and other rulings, and excessive damages awards. We are unable to predict the date on which the trial court will decide the motion for post-trial relief. Subject to the nature and extent of the trial court's ruling on post-trial relief, we intend to file Notices of Appeal to the First District Appellate Court in Illinois within 30 days of such ruling. We have taken into consideration the events that have occurred after the reporting period and before the financial statements were issued. Based on the status of the first individual case, we believe a loss is not probable, but the range of loss for this case could be from $0 to $358.7 million, plus potential post-judgment interest. We have not recorded a reserve with respect to this litigation as a number of factors (including post-trial relief and the appeals processes which are anticipated to take at least eighteen months or longer) could significantly change the assessment of damages and the ultimate outcome of the case. The Company believes the verdict in the first trial is not predictive of potential future verdicts in the other Illinois EO tort cases. The cases will be presided over by different judges, tried by different counsel presenting different evidence and fact and expert witness testimony at trial, and decided by different juries. Each plaintiff’s claim involves unique facts and evidence including but not limited to, the circumstances of plaintiff’s alleged exposure, the type and severity of the plaintiff’s disease and the plaintiff’s medical history and course of treatment. As a result, we believe that loss in such subsequent cases is not probable and it is not possible to estimate the range of loss. Due to the uncertainties associated with the amount of any such liability and/or the nature of any other remedy which may be imposed in such litigation, any potential liability determined to be attributable to the Company arising out of such litigation may have a material adverse effect on the Company’s results of operations, liquidity or financial condition. An estimate of the potential impact on the Company’s results of operations, liquidity or financial condition cannot be made due to the aforementioned uncertainties. The second individual trial began in Cook County, IL on October 6, 2022 and is underway. Subsequent individual trials are currently scheduled to begin in January 2023 and April 2023. At a recent hearing, the court indicated that the claims of small groups of plaintiffs should be tried jointly, starting in late May 2023. The parties have been instructed to confer to identify plaintiffs whose claims could be tried jointly because the details of their individual claims are similar. We expect to know more in mid-November about whether joint trials are possible and when they will be scheduled. Even if joint trials proceed, they will remain individual actions, not class actions. 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 one 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 and an immediate appeal of a discrete procedural issue is being pursued by the defendants. One personal injury case is pending in Gwinnett County and is scheduled for trial in October 2023. The remaining personal injury case 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. All parties have filed motions for summary judgment which remain pending. Trial is scheduled to begin on January 24, 2023. 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 Sotera Health Company and another defendant is pending and all other motions to dismiss have been denied. A Scheduling Order was entered on September 13, 2022, including a June 3, 2024 trial date. * * * Our insurance for litigation related to alleged environmental liabilities, like the litigation pending in Illinois, Georgia and New Mexico described above has limits of $10.0 million per occurrence and $20.0 million in the aggregate. The per occurrence limit related to the Willowbrook, Illinois litigation was fully utilized by June 30, 2020. The remaining $10.0 million limit is currently being utilized for occurrences related to the EO litigation in Georgia and New Mexico described above. As of September 30, 2022, we have utilized approximately $7.5 million of the remaining $10.0 million limit. Our insurance for future alleged environmental liabilities excludes coverage for EO claims. In addition, we are pursuing other insurance coverage for our legal expenses related to the EO tort litigation. In 2021, Sterigenics U.S., LLC filed an insurance coverage lawsuit in the U.S. District Court for the Northern District of Illinois relating to two commercial general liability policies issued in the 1980s. On August 3, 2022, the Court issued a Memorandum Opinion and Order concluding that the insurer owes Sterigenics U.S., LLC and another insured party a duty to defend the Willowbrook, Illinois litigation, which may allow us to recover defense costs related to that litigation.

Financial Instruments and Finan

Financial Instruments and Financial Risk	9 Months Ended
	Sep. 30, 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 May 2022, we entered into two interest rate cap agreements with a combined notional amount of $1,000.0 million for a total option premium of $4.1 million. The interest rate caps have a forward start date of July 31, 2023 and expire on July 31, 2024. We have designated these interest rate caps as cash flow hedges designed to hedge the variability of cash flows attributable to changes in the benchmark interest rate of our Term Loan. Under the current terms of the loan agreement, the benchmark interest rate index is expected to transition from LIBOR to the term Secured Overnight Financing Rate (“SOFR”) at the earlier of June 30, 2023 or the Company’s election to “early opt-in” to SOFR. Accordingly, the interest rate cap agreements hedge the variability of cash flows attributable to changes in SOFR by limiting our cash flow exposure related to the term SOFR under a portion of our variable rate borrowings to 3.5%. 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 derivatives 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 recorded in “Interest expense, net” in the Consolidated Statements of Operations and Comprehensive Income (Loss). 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 limit 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%. 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 were 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 September 30, 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 (Loss). The following table provides a summary of the notional and fair values of our derivative instruments: September 30, 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 $ 2,000.0 (a) $ 31,920 $ — $ 1,000.0 $ 2,322 $ — Derivatives not designated as hedging instruments: Interest rate caps $ 1,000.0 $ 7,752 $ — $ 1,500.0 $ 1,654 $ — Embedded derivatives 183.6 (b) 3,522 4,745 144.4 496 — Total $ 3,183.6 $ 43,194 $ 4,745 $ 2,644.4 $ 4,472 $ — (a) $1,000.0 million and $1,000.0 million notional amount of interest rate caps designated as hedging instruments have forward start dates beginning on December 31, 2022 and July 31, 2023, respectively. (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 the Consolidated Balance Sheets depending upon their respective maturity dates. 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 the Consolidated Statements of Operations and Comprehensive Income (Loss): (thousands of U.S. dollars) Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Unrealized loss (gain) on interest rate caps recorded in interest expense, net $ 3,348 $ (116) $ (6,098) $ 267 Unrealized loss (gain) on embedded derivatives recorded in other expense (income), net 359 1,189 1,776 (424) Realized gain on interest rate caps recorded in interest expense, net (4,473) — (5,752) — Realized loss (gain) on foreign currency forward contracts recorded in foreign exchange (gain) loss 4,157 762 3,662 (1,381) The following table summarizes the net gains on our cash flow hedges recognized in “Other comprehensive income (loss)” during the period: (thousands of U.S. dollars) Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Unrealized gain on interest rate derivatives recorded in other comprehensive income (loss), net of tax $ 9,408 $ — $ 18,765 $ — We expect to reclassify approximately $22.8 million of after-tax net gains on derivative instruments from accumulated other comprehensive income (loss) 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 September 30, 2022 and December 31, 2021, accounts receivable was net of an allowance for uncollectible accounts of $1.4 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 September 30, 2022 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Interest rate caps $ 31,920 — $ 31,920 — Derivatives not designated as hedging instruments (b) Interest rate caps 7,752 — 7,752 — Embedded derivative assets 3,522 — 3,522 — Embedded derivative liabilities 4,745 — 4,745 — Long-Term Debt (c) Term loan, due 2026 1,746,109 — 1,604,421 — Other long-term debt 446 — 446 — Finance Lease Obligations (with current portion) (d) 56,526 — 56,526 — 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) Interest rate caps $ 2,322 $ — $ 2,322 $ — Derivatives not designated as hedging instruments (b) Interest rate caps 1,654 — 1,654 — Embedded derivative liabilities 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) 42,047 — 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 that 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 (Loss). 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 upon 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	9 Months Ended
	Sep. 30, 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 pharmaceutical industries. For the three months ended September 30, 2022, three customers reported within the Nordion segment individually represented 10% or more of the segment’s total net revenues. These customers represented 21.0%, 14.7%, and 10.1% of the total segment’s external net revenues for the three months ended September 30, 2022. For the three months ended September 30, 2021, four customers reported within the Nordion segment individually represented 10% or more of the segment’s total net revenues. These customers represented 20.4%, 12.8%, 12.8%, and 10.3% of the total segment’s external net revenues for the three months ended September 30, 2021. For the nine months ended September 30, 2022, four customers reported within the Nordion segment individually represented 10% or more of the segment’s total net revenues. These customers represented 17.1%, 16.2%, 11.8% , and 11.7% of the total segment’s external net revenues for the nine months ended September 30, 2022. For the nine months ended September 30, 2021, five customers reported within the Nordion segment individually represented 10% or more of the segment’s total net revenues. These customers represented 13.2%, 12.8%, 12.6%, 12.3%, and 10.5% of the total segment's external net revenues for the nine months ended September 30, 2021. Financial information for each of our segments is presented in the following table: Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Segment revenues (a) Sterigenics $ 157,723 $ 145,314 $ 464,977 $ 421,647 Nordion 35,071 28,768 119,551 103,811 Nelson Labs 55,910 52,082 167,569 164,771 Total net revenues $ 248,704 $ 226,164 $ 752,097 $ 690,229 Segment income (b) Sterigenics $ 85,587 $ 79,344 $ 250,088 $ 227,374 Nordion 20,294 16,331 69,179 61,285 Nelson Labs 19,271 20,999 57,369 67,895 Total segment income $ 125,152 $ 116,674 $ 376,636 $ 356,554 (a) Revenues are reported net of intersegment sales. Our Nordion segment recognized $7.4 million and $3.7 million in revenues from sales to our Sterigenics segment for the three months ended September 30, 2022 and 2021, and $38.7 million and $21.2 million in revenues from sales to our Sterigenics segment for the nine months ended September 30, 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 these 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, investor relations, 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 nine months ended September 30, 2022 and 2021 were as follows: Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 Sterigenics $ 90,444 $ 48,552 Nordion 12,045 7,531 Nelson Labs 8,153 4,815 Total capital expenditures $ 110,642 $ 60,898 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 September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Segment income $ 125,152 $ 116,674 $ 376,636 $ 356,554 Less adjustments: Interest expense, net (a) 20,080 18,140 53,974 58,585 Depreciation and amortization (b) 36,104 37,634 109,092 112,756 Share-based compensation (c) 4,616 3,547 14,955 10,489 Gain on foreign currency and derivatives not designated as hedging instruments, net (d) 3,194 1,881 (4,788) 885 Acquisition and divestiture related charges, net (e) 447 (2,662) 978 (2,003) Business optimization project expenses (f) 1,035 244 1,609 780 Plant closure expenses (g) 2,627 266 3,776 1,564 Impairment of investment in unconsolidated affiliate (h) — — 9,613 — Loss on extinguishment of debt (i) — 6,365 — 20,677 Professional services relating to EO sterilization facilities (j) 14,501 9,449 50,238 33,492 Accretion of asset retirement obligation (k) 526 598 1,644 1,751 COVID-19 expenses (l) 6 109 154 596 Consolidated income before taxes $ 42,016 $ 41,103 $ 135,391 $ 116,982 (a) The three and nine months ended September 30, 2022 excludes $3.3 million of unrealized loss and $6.1 million of unrealized gain, respectively, 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 and losses 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, and (iv) a $3.4 million gain recognized in the third quarter of 2021 related to the settlement of an insurance claim for Nordion that existed at the time of our acquisition of the business in 2014. (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 recent acquisitions, operating structure realignment and other process enhancement projects. (g) Represents decommissioning costs, 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 an impairment charge on our equity method investment in a joint venture. Refer to Note 1, “Basis of Presentation”. (i) Represents expenses incurred in connection with the repricing of our Term Loan in January 2021 and full redemption of the First Lien Notes in August 2021, including a prepayment premium and accelerated amortization of prior debt issuance and discount costs. (j) Represents litigation and other professional fees associated with our EO sterilization facilities. See Note 16, “Commitments and Contingencies” . (k) Represents non-cash accretion of asset retirement obligations related to gamma and EO 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.

Basis of Presentation (Policies

Basis of Presentation (Policies)	9 Months Ended
	Sep. 30, 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.
Adoption of Accounting Standard Updates and ASU’s Issued But Not Yet Adopted	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. ASUs 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)	9 Months Ended
	Sep. 30, 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 and nine months ended September 30, 2022 and 2021: (thousands of U.S. dollars) Three Months Ended September 30, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 157,723 $ 33,830 $ — $ 191,553 Over time — 1,241 55,910 57,151 Total $ 157,723 $ 35,071 $ 55,910 $ 248,704 (thousands of U.S. dollars) Three Months Ended September 30, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 145,314 $ 28,768 $ — $ 174,082 Over time — — 52,082 52,082 Total $ 145,314 $ 28,768 $ 52,082 $ 226,164 (thousands of U.S. dollars) Nine Months Ended September 30, 2022 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 464,977 $ 113,501 $ — $ 578,478 Over time — 6,050 167,569 173,619 Total $ 464,977 $ 119,551 $ 167,569 $ 752,097 (thousands of U.S. dollars) Nine Months Ended September 30, 2021 Sterigenics Nordion Nelson Labs Consolidated Point in time $ 421,647 $ 102,439 $ — $ 524,086 Over time — 1,372 164,771 166,143 Total $ 421,647 $ 103,811 $ 164,771 $ 690,229

Inventories (Tables)

Inventories (Tables)	9 Months Ended
	Sep. 30, 2022
Inventory Disclosure [Abstract]
Schedule of Inventories	Inventories consisted primarily of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Raw materials and supplies $ 31,449 $ 41,514 Work-in-process 389 3,919 Finished goods 5,429 8,979 37,267 54,412 Reserve for excess and obsolete inventory (114) (124) Inventories, net $ 37,153 $ 54,288

Prepaid Expenses and Other Cu_2

Prepaid Expenses and Other Current Assets (Tables)	9 Months Ended
	Sep. 30, 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 primarily of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Prepaid taxes $ 29,735 $ 24,937 Prepaid business insurance 1,871 10,707 Prepaid rent 1,111 920 Customer contract assets 22,387 15,565 Insurance and indemnification receivables 4,361 3,144 Current deposits 760 623 Prepaid maintenance contracts 385 279 Value added tax receivable 759 2,512 Prepaid software licensing 2,055 2,055 Stock supplies 3,597 3,374 Embedded derivatives 3,522 496 Other 11,130 7,311 Prepaid expenses and other current assets $ 81,673 $ 71,923

Goodwill and Other Intangible_2

Goodwill and Other Intangible Assets (Tables)	9 Months Ended
	Sep. 30, 2022
Goodwill and Intangible Assets Disclosure [Abstract]
Schedule of Goodwill	Changes to goodwill during the nine months ended September 30, 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 — — 4,645 4,645 Changes due to foreign currency exchange rates (5,982) (21,748) (4,766) (32,496) Goodwill at September 30, 2022 $ 654,761 $ 267,157 $ 170,551 $ 1,092,469
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 September 30, 2022 Finite-lived intangible assets Customer relationships $ 644,236 $ 402,253 Proprietary technology 84,392 48,446 Trade names 2,550 574 Land-use rights 8,715 1,579 Sealed source and supply agreements 201,496 88,712 Other 4,439 1,746 Total finite-lived intangible assets 945,828 543,310 Indefinite-lived intangible assets Regulatory licenses and other (a) 75,888 — Trade names / trademarks 25,349 — Total indefinite-lived intangible assets 101,237 — Total $ 1,047,065 $ 543,310 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 September 30, 2022 Finite-lived intangible assets Customer relationships $ 644,236 $ 402,253 Proprietary technology 84,392 48,446 Trade names 2,550 574 Land-use rights 8,715 1,579 Sealed source and supply agreements 201,496 88,712 Other 4,439 1,746 Total finite-lived intangible assets 945,828 543,310 Indefinite-lived intangible assets Regulatory licenses and other (a) 75,888 — Trade names / trademarks 25,349 — Total indefinite-lived intangible assets 101,237 — Total $ 1,047,065 $ 543,310 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 $ 19,779 2023 79,485 2024 78,709 2025 41,907 2026 21,872 Thereafter 160,766 Total $ 402,518

Accrued Liabilities (Tables)

Accrued Liabilities (Tables)	9 Months Ended
	Sep. 30, 2022
Payables and Accruals [Abstract]
Schedule of Accrued Liabilities	Accrued liabilities consisted of the following: (thousands of U.S. dollars) September 30, 2022 December 31, 2021 Accrued employee compensation $ 28,589 $ 33,334 Legal reserves 3,267 3,259 Accrued interest expense 993 10,755 Embedded derivatives 4,745 — Professional fees 8,196 4,314 Accrued utilities 1,885 1,797 Insurance accrual 2,220 2,068 Accrued taxes 3,196 2,209 Other 3,671 4,125 Accrued liabilities $ 56,762 $ 61,861

Long-Term Debt (Tables)

Long-Term Debt (Tables)	9 Months Ended
	Sep. 30, 2022
Debt Disclosure [Abstract]
Schedule of Long-term Debt Instruments	Long-term debt consisted of the following: (thousands of U.S. dollars) September 30, 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 current portion — — Less unamortized debt issuance costs and debt discounts (16,995) (20,016) Total long-term debt, less debt issuance costs and debt discounts $ 1,746,555 $ 1,743,534
Schedule of Maturities of Long-term Debt	Aggregate maturities of the Company’s long-term debt, excluding debt discounts, as of September 30, 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)	9 Months Ended
	Sep. 30, 2022
Postemployment Benefits [Abstract]
Schedule of Net Benefit Costs	The components of net periodic pension cost for the defined benefit plans for the three and nine months ended September 30, 2022 and 2021 were as follows: Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Service cost $ 242 $ 300 $ 738 $ 905 Interest cost 1,848 1,622 5,640 4,897 Expected return on plan assets (3,595) (3,577) (10,975) (10,799) Amortization of net actuarial loss — 269 — 811 Net periodic benefit $ (1,505) $ (1,386) $ (4,597) $ (4,186) Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Service cost $ 4 $ 7 $ 12 $ 21 Interest cost 63 59 193 179 Amortization of net actuarial loss (gain) (2) 9 (6) 26 Net periodic benefit cost $ 65 $ 75 $ 199 $ 226

Other Comprehensive Income (L_2

Other Comprehensive Income (Loss) (Tables)	9 Months Ended
	Sep. 30, 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 Derivatives Total Beginning balance – July 1, 2022 $ (17,323) $ (97,452) $ 9,761 $ (105,014) Other comprehensive income (loss) before reclassifications 1,067 (69,460) 9,408 (58,985) Amounts reclassified from accumulated other comprehensive income (loss) (2) (a) — — (2) Net current-period other comprehensive income (loss) 1,065 (69,460) 9,408 (58,987) Ending balance – September 30, 2022 $ (16,258) $ (166,912) $ 19,169 $ (164,001) Beginning balance – January 1, 2022 $ (17,581) $ (66,389) $ 404 $ (83,566) Other comprehensive income (loss) before reclassifications 1,329 (100,523) 18,765 (80,429) Amounts reclassified from accumulated other comprehensive income (loss) (6) (a) — — (6) Net current-period other comprehensive income (loss) 1,323 (100,523) 18,765 (80,435) Ending balance – September 30, 2022 $ (16,258) $ (166,912) $ 19,169 $ (164,001) (thousands of U.S. dollars) Defined Benefit Plans Foreign Currency Translation Interest Rate Derivatives Total Beginning balance – July 1, 2021 $ (44,813) $ (32,655) $ — $ (77,468) Other comprehensive income (loss) before reclassifications 1,105 (29,867) — (28,762) Amounts reclassified from accumulated other comprehensive income (loss) 278 (a) — — 278 Net current-period other comprehensive income (loss) 1,383 (29,867) — (28,484) Ending balance – September 30, 2021 $ (43,430) $ (62,522) $ — $ (105,952) Beginning balance – January 1, 2021 $ (44,143) $ (49,699) $ — $ (93,842) Other comprehensive income (loss) before reclassifications (124) (12,823) — (12,947) Amounts reclassified from accumulated other comprehensive income (loss) 837 (a) — — 837 Net current-period other comprehensive income (loss) 713 (12,823) — (12,110) Ending balance – September 30, 2021 $ (43,430) $ (62,522) $ — $ (105,952) (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 (Loss).

Share-Based Compensation (Table

Share-Based Compensation (Tables)	9 Months Ended
	Sep. 30, 2022
Share-Based Payment Arrangement [Abstract]
Schedule of Restricted Stock Activity	A summary of the activity for the nine months ended September 30, 2022 related to the restricted stock awards distributed to 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 (32,614) (925,544) Vested (345,926) — Unvested at September 30, 2022 827,549 1,098,415 Number of Shares Weighted Average Grant Date Fair Value Unvested at December 31, 2021 640,122 $ 23.19 Granted 954,685 20.57 Forfeited (145,656) 21.90 Vested (89,121) 24.13 Unvested at September 30, 2022 1,360,030 $ 21.43
Schedule of Stock Option Activity	The following table summarizes our stock option activity for the nine months ended September 30, 2022: Number of Shares Weighted Average Exercise Price At December 31, 2021 2,423,256 $ 23.02 Granted 1,445,887 19.96 Forfeited (454,953) 22.08 Exercised — — At September 30, 2022 3,414,190 $ 21.85 As of September 30, 2022, there were 0.5 million stock options vested or exercisable.

Earnings Per Share (Tables)

Earnings Per Share (Tables)	9 Months Ended
	Sep. 30, 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 Nine Months Ended in thousands of U.S. dollars and share amounts (except per share amounts) September 30, September 30, September 30, September 30, Earnings: Net income $ 25,090 $ 27,444 $ 86,149 $ 81,124 Less: Net income attributable to noncontrolling interests — — — 239 Less: Allocation to participating securities 223 343 862 1,089 Net income attributable to Sotera Health Company common shareholders $ 24,867 $ 27,101 $ 85,287 $ 79,796 Weighted Average Common Shares: Weighted-average common shares outstanding - basic 280,142 279,381 279,988 279,097 Dilutive effect of potential common shares 30 179 105 156 Weighted-average common shares outstanding - diluted 280,172 279,560 280,093 279,253 Earnings per Common Share: Net income per common share attributable to Sotera Health Company common shareholders - basic $ 0.09 $ 0.10 $ 0.31 $ 0.29 Net income per common share attributable to Sotera Health Company common shareholders - diluted 0.09 0.10 0.31 0.29
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 Nine Months Ended in thousands of share amounts September 30, September 30, September 30, September 30, Stock options 3,526 2,403 3,399 2,399 RSUs 1,121 5 34 7 Total anti-dilutive securities 4,647 2,408 3,433 2,406

Financial Instruments and Fin_2

Financial Instruments and Financial Risk (Tables)	9 Months Ended
	Sep. 30, 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: September 30, 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 $ 2,000.0 (a) $ 31,920 $ — $ 1,000.0 $ 2,322 $ — Derivatives not designated as hedging instruments: Interest rate caps $ 1,000.0 $ 7,752 $ — $ 1,500.0 $ 1,654 $ — Embedded derivatives 183.6 (b) 3,522 4,745 144.4 496 — Total $ 3,183.6 $ 43,194 $ 4,745 $ 2,644.4 $ 4,472 $ — (a) $1,000.0 million and $1,000.0 million notional amount of interest rate caps designated as hedging instruments have forward start dates beginning on December 31, 2022 and July 31, 2023, respectively. (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 the Consolidated Statements of Operations and Comprehensive Income (Loss): (thousands of U.S. dollars) Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Unrealized loss (gain) on interest rate caps recorded in interest expense, net $ 3,348 $ (116) $ (6,098) $ 267 Unrealized loss (gain) on embedded derivatives recorded in other expense (income), net 359 1,189 1,776 (424) Realized gain on interest rate caps recorded in interest expense, net (4,473) — (5,752) — Realized loss (gain) on foreign currency forward contracts recorded in foreign exchange (gain) loss 4,157 762 3,662 (1,381) The following table summarizes the net gains on our cash flow hedges recognized in “Other comprehensive income (loss)” during the period: (thousands of U.S. dollars) Three Months Ended September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Unrealized gain on interest rate derivatives recorded in other comprehensive income (loss), net of tax $ 9,408 $ — $ 18,765 $ —
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 September 30, 2022 Fair Value (thousands of U.S. dollars) Carrying Level 1 Level 2 Level 3 Derivatives designated as hedging instruments (a) Interest rate caps $ 31,920 — $ 31,920 — Derivatives not designated as hedging instruments (b) Interest rate caps 7,752 — 7,752 — Embedded derivative assets 3,522 — 3,522 — Embedded derivative liabilities 4,745 — 4,745 — Long-Term Debt (c) Term loan, due 2026 1,746,109 — 1,604,421 — Other long-term debt 446 — 446 — Finance Lease Obligations (with current portion) (d) 56,526 — 56,526 — 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) Interest rate caps $ 2,322 $ — $ 2,322 $ — Derivatives not designated as hedging instruments (b) Interest rate caps 1,654 — 1,654 — Embedded derivative liabilities 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) 42,047 — 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 that 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 (Loss). 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 upon 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)	9 Months Ended
	Sep. 30, 2022
Segment Reporting [Abstract]
Schedule of Segment Reporting Information, by Segment	Financial information for each of our segments is presented in the following table: Three Months Ended September 30, Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 2022 2021 Segment revenues (a) Sterigenics $ 157,723 $ 145,314 $ 464,977 $ 421,647 Nordion 35,071 28,768 119,551 103,811 Nelson Labs 55,910 52,082 167,569 164,771 Total net revenues $ 248,704 $ 226,164 $ 752,097 $ 690,229 Segment income (b) Sterigenics $ 85,587 $ 79,344 $ 250,088 $ 227,374 Nordion 20,294 16,331 69,179 61,285 Nelson Labs 19,271 20,999 57,369 67,895 Total segment income $ 125,152 $ 116,674 $ 376,636 $ 356,554 (a) Revenues are reported net of intersegment sales. Our Nordion segment recognized $7.4 million and $3.7 million in revenues from sales to our Sterigenics segment for the three months ended September 30, 2022 and 2021, and $38.7 million and $21.2 million in revenues from sales to our Sterigenics segment for the nine months ended September 30, 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 these 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 nine months ended September 30, 2022 and 2021 were as follows: Nine Months Ended September 30, (thousands of U.S. dollars) 2022 2021 Sterigenics $ 90,444 $ 48,552 Nordion 12,045 7,531 Nelson Labs 8,153 4,815 Total capital expenditures $ 110,642 $ 60,898
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 September 30, Nine Months Ended September 30, 2022 2021 2022 2021 Segment income $ 125,152 $ 116,674 $ 376,636 $ 356,554 Less adjustments: Interest expense, net (a) 20,080 18,140 53,974 58,585 Depreciation and amortization (b) 36,104 37,634 109,092 112,756 Share-based compensation (c) 4,616 3,547 14,955 10,489 Gain on foreign currency and derivatives not designated as hedging instruments, net (d) 3,194 1,881 (4,788) 885 Acquisition and divestiture related charges, net (e) 447 (2,662) 978 (2,003) Business optimization project expenses (f) 1,035 244 1,609 780 Plant closure expenses (g) 2,627 266 3,776 1,564 Impairment of investment in unconsolidated affiliate (h) — — 9,613 — Loss on extinguishment of debt (i) — 6,365 — 20,677 Professional services relating to EO sterilization facilities (j) 14,501 9,449 50,238 33,492 Accretion of asset retirement obligation (k) 526 598 1,644 1,751 COVID-19 expenses (l) 6 109 154 596 Consolidated income before taxes $ 42,016 $ 41,103 $ 135,391 $ 116,982 (a) The three and nine months ended September 30, 2022 excludes $3.3 million of unrealized loss and $6.1 million of unrealized gain, respectively, 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 and losses 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, and (iv) a $3.4 million gain recognized in the third quarter of 2021 related to the settlement of an insurance claim for Nordion that existed at the time of our acquisition of the business in 2014. (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 recent acquisitions, operating structure realignment and other process enhancement projects. (g) Represents decommissioning costs, 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 an impairment charge on our equity method investment in a joint venture. Refer to Note 1, “Basis of Presentation”. (i) Represents expenses incurred in connection with the repricing of our Term Loan in January 2021 and full redemption of the First Lien Notes in August 2021, including a prepayment premium and accelerated amortization of prior debt issuance and discount costs. (j) Represents litigation and other professional fees associated with our EO sterilization facilities. See Note 16, “Commitments and Contingencies” . (k) Represents non-cash accretion of asset retirement obligations related to gamma and EO 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.

Basis of Presentation (Details)

Basis of Presentation (Details) $ in Thousands			1 Months Ended	3 Months Ended			9 Months Ended
	May 18, 2021 subsidiary	Mar. 11, 2021	Aug. 31, 2018	Sep. 30, 2022 USD ($)	Jun. 30, 2022 USD ($) subsidiary	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($) segment	Sep. 30, 2021 USD ($)	Jul. 31, 2020
Accounting Policies [Abstract]
Number of operating segments | segment							3
Number of reportable segments | segment							3
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Impairment of investment in unconsolidated affiliate				$ 0		$ 0	$ 9,613	$ 0
Unnamed E-Beam Joint Venture
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Ownership percentage (as percent)									60%
Auralux
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Investments, fair value disclosure					$ 0
Impairment of investment in unconsolidated affiliate					$ 9,600
Nelson Fairfield
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percent of purchase of interest (as percent)		15%	85%
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 (as percent)	15%				15%
China | Subsidiary Two
Consolidation, Less than Wholly Owned Subsidiary, Parent Ownership Interest, Effects of Changes, Net [Line Items]
Percent of purchase of interest (as percent)	33%				33%

Revenue Recognition (Details)

Revenue Recognition (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021	Dec. 31, 2021
Disaggregation of Revenue [Line Items]
Total net revenues	$ 248,704	$ 226,164	$ 752,097	$ 690,229
Customer contract assets	22,387		22,387		$ 15,565
Deferred revenue	5,347		5,347		$ 8,669
Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	191,553	174,082	578,478	524,086
Over time
Disaggregation of Revenue [Line Items]
Total net revenues	57,151	52,082	173,619	166,143
Sterigenics
Disaggregation of Revenue [Line Items]
Total net revenues	157,723	145,314	464,977	421,647
Sterigenics | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	157,723	145,314	464,977	421,647
Sterigenics | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	0	0	0	0
Nordion
Disaggregation of Revenue [Line Items]
Total net revenues	35,071	28,768	119,551	103,811
Nordion | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	33,830	28,768	113,501	102,439
Nordion | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	1,241	0	6,050	1,372
Nelson Labs
Disaggregation of Revenue [Line Items]
Total net revenues	55,910	52,082	167,569	164,771
Nelson Labs | Point in time
Disaggregation of Revenue [Line Items]
Total net revenues	0	0	0	0
Nelson Labs | Over time
Disaggregation of Revenue [Line Items]
Total net revenues	$ 55,910	$ 52,082	$ 167,569	$ 164,771

Acquisitions (Details)

Acquisitions (Details) $ in Thousands					1 Months Ended	3 Months Ended	9 Months Ended		16 Months Ended
	Nov. 04, 2021 USD ($)	May 18, 2021 USD ($) subsidiary	Mar. 11, 2021 USD ($)	Mar. 08, 2021 USD ($)	Aug. 31, 2018	Jun. 30, 2022 subsidiary	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Dec. 31, 2021 USD ($)
Business Acquisition [Line Items]
Goodwill							$ 1,092,469		$ 1,092,469	$ 1,120,320
Acquisition of noncontrolling interests								$ 8,578	2,800
Payments to acquire businesses, net of cash acquired							0	13,530
Additional Paid-In Capital
Business Acquisition [Line Items]
Acquisition of noncontrolling interests								$ 5,772	(5,800)
Nelson Fairfield
Business Acquisition [Line Items]
Percent of purchase of interest (as percent)			15%		85%
China
Business Acquisition [Line Items]
Number of subsidiaries with non-controlling interest | subsidiary		2				2
Purchase price		$ 8,600
Amount of demand note cancelled		$ 800
Percent of consideration transferred on acquisition date (as percent)		90%
Percent of consideration settled in post-closing payment							200		200
China | Subsidiary One
Business Acquisition [Line Items]
Percent of purchase of interest (as percent)		15%				15%
China | Subsidiary Two
Business Acquisition [Line Items]
Percent of purchase of interest (as percent)		33%				33%
China | China Subsidiaries
Business Acquisition [Line Items]
Ownership percentage by parent (as percent)		100%
Regulatory Compliance Associates Inc R C A
Business Acquisition [Line Items]
Purchase price	$ 30,600
Cash acquired from acquisition	$ 600
Goodwill							25,300		25,300
Regulatory Compliance Associates Inc R C A | Customer relationships
Business Acquisition [Line Items]
Finite-lived intangibles							6,400		6,400
Nelson Fairfield
Business Acquisition [Line Items]
Purchase price			$ 12,400
Step acquisition, gain			$ 1,200
Financial instruments subject to mandatory redemption, settlement terms, share value, amount										$ 13,600
Business Combination, Step Acquisition, Period Of Acquiring Remaining Interest					3 years
BioScience
Business Acquisition [Line Items]
Goodwill							$ 8,400		$ 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	Sep. 30, 2022	Dec. 31, 2021
Inventory Disclosure [Abstract]
Raw materials and supplies	$ 31,449	$ 41,514
Work-in-process	389	3,919
Finished goods	5,429	8,979
Inventories, gross	37,267	54,412
Reserve for excess and obsolete inventory	(114)	(124)
Inventories, net	$ 37,153	$ 54,288

Prepaid Expenses and Other Cu_3

Prepaid Expenses and Other Current Assets (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Prepaid taxes	$ 29,735	$ 24,937
Prepaid business insurance	1,871	10,707
Prepaid rent	1,111	920
Customer contract assets	22,387	15,565
Insurance and indemnification receivables	4,361	3,144
Current deposits	760	623
Prepaid maintenance contracts	385	279
Value added tax receivable	759	2,512
Prepaid software licensing	2,055	2,055
Stock supplies	3,597	3,374
Embedded derivatives	3,522	496
Other	11,130	7,311
Prepaid expenses and other current assets	$ 81,673	$ 71,923

Goodwill and Other Intangible_3

Goodwill and Other Intangible Assets - Goodwill (Details) $ in Thousands	9 Months Ended
	Sep. 30, 2022 USD ($)
Goodwill [Roll Forward]
Beginning balance	$ 1,120,320
Changes due to foreign currency exchange rates	(32,496)
Ending balance	1,092,469
Regulatory Compliance Associates Inc R C A
Goodwill [Roll Forward]
RCA acquisition measurement period adjustments	4,645
Ending balance	25,300
Sterigenics
Goodwill [Roll Forward]
Beginning balance	660,743
Changes due to foreign currency exchange rates	(5,982)
Ending balance	654,761
Sterigenics | Regulatory Compliance Associates Inc R C A
Goodwill [Roll Forward]
RCA acquisition measurement period adjustments	0
Nordion
Goodwill [Roll Forward]
Beginning balance	288,905
Changes due to foreign currency exchange rates	(21,748)
Ending balance	267,157
Nordion | Regulatory Compliance Associates Inc R C A
Goodwill [Roll Forward]
RCA acquisition measurement period adjustments	0
Nelson Labs
Goodwill [Roll Forward]
Beginning balance	170,672
Changes due to foreign currency exchange rates	(4,766)
Ending balance	170,551
Nelson Labs | Regulatory Compliance Associates Inc R C A
Goodwill [Roll Forward]
RCA acquisition measurement period adjustments	$ 4,645

Goodwill and Other Intangible_4

Goodwill and Other Intangible Assets - Intangibles (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 945,828	$ 1,015,408
Accumulated Amortization	543,310	524,507
Gross Carrying Amount	101,237	107,943
Total	1,047,065	1,123,351
Regulatory licenses and other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 75,888	82,110
Renewal term	10 years
Trade names / trademarks
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	$ 25,349	25,833
Customer relationships
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	644,236	668,628
Accumulated Amortization	402,253	365,935
Proprietary technology
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	84,392	88,826
Accumulated Amortization	48,446	44,866
Trade names
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	2,550	145
Accumulated Amortization	574	116
Land-use rights
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	8,715	9,744
Accumulated Amortization	1,579	1,586
Sealed source and supply agreements
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	201,496	241,611
Accumulated Amortization	88,712	109,838
Other
Acquired Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	4,439	6,454
Accumulated Amortization	$ 1,746	$ 2,166

Goodwill and Other Intangible_5

Goodwill and Other Intangible Assets - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets			$ 61,596	$ 65,299
Finite-lived intangible assets, remaining amortization period			8 years 6 months
Other
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 20,200	$ 21,200	$ 61,600	65,300
Other | Cost of Revenue
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	4,500	5,300	14,300	17,200
Other | Selling, General and Administrative Expenses
Finite-Lived Intangible Assets [Line Items]
Amortization of intangible assets	$ 15,700	$ 15,900	$ 47,300	$ 48,100

Goodwill and Other Intangible_6

Goodwill and Other Intangible Assets - Future Amortization Expense (Details) $ in Thousands	Sep. 30, 2022 USD ($)
Goodwill and Intangible Assets Disclosure [Abstract]
For the remainder of 2022	$ 19,779
2023	79,485
2024	78,709
2025	41,907
2026	21,872
Thereafter	160,766
Total	$ 402,518

Accrued Liabilities (Details)

Accrued Liabilities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Payables and Accruals [Abstract]
Accrued employee compensation	$ 28,589	$ 33,334
Legal reserves	3,267	3,259
Accrued interest expense	993	10,755
Embedded derivatives	4,745	0
Professional fees	8,196	4,314
Accrued utilities	1,885	1,797
Insurance accrual	2,220	2,068
Accrued taxes	3,196	2,209
Other	3,671	4,125
Accrued liabilities	$ 56,762	$ 61,861

Long-Term Debt - Schedule of De

Long-Term Debt - Schedule of Debt (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Instrument [Line Items]
Total long-term debt	$ 1,763,550	$ 1,763,550
Less current portion	0	0
Less unamortized debt issuance costs and debt discounts	(16,995)	(20,016)
Total	1,746,555	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 ($)

3 Months Ended

9 Months Ended

Sep. 20, 2022

Sep. 19, 2022

Mar. 26, 2021

Jan. 20, 2021

Jan. 19, 2021

Sep. 30, 2022

Sep. 30, 2021

Sep. 30, 2022

Sep. 30, 2021

Dec. 31, 2021

Jul. 31, 2020

Dec. 13, 2019

Debt Instrument [Line Items]

Long-term debt, gross

$ 1,763,550,000

$ 1,763,550,000

$ 1,763,550,000

Ethylene Oxide Tort Litigation - Illinois | Pending Litigation

Debt Instrument [Line Items]

Base amount for default

100,000,000

$ 100,000,000

Triggering period for default

60 days

Amount awarded to other party

$ 358,700,000

$ 358,700,000

Senior Secured Credit Facilities | Term Loan

Debt Instrument [Line Items]

Debt issuance costs

2,300,000

$ 2,300,000

2,700,000

Senior Secured Credit Facilities | Secured Debt

Debt Instrument [Line Items]

Debt discount

14,700,000

14,700,000

17,300,000

Term loan, due 2026 | Term Loan

Debt Instrument [Line Items]

Long-term debt, gross

$ 1,763,100,000

$ 1,763,100,000

1,763,100,000

Weighted average interest rate

4.96%

3.25%

3.92%

3.51%

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

1%

0.50%

0.50%

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%

LIBOR floor

1%

First Lien Notes due 2026 | Secured Debt | LIBOR

Debt Instrument [Line Items]

Basis spread on variable rate

2.75%

6%

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%

Revolving Credit Facility | Senior Secured Credit Facilities

Debt Instrument [Line Items]

Maximum borrowing capacity

$ 347,500,000

Capitalized debt issuance costs

$ 0

Letters of credit outstanding, amount

$ 67,600,000

$ 67,600,000

Unused borrowing capacity

$ 279,900,000

$ 279,900,000

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%

Long-Term Debt - First Lien Not

Long-Term Debt - First Lien Notes (Details) - Secured Debt - First Lien Notes due 2026 - USD ($)			9 Months Ended
	Mar. 26, 2021	Jul. 31, 2020	Sep. 30, 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%
Weighted average interest rate			7%
LIBOR
Debt Instrument [Line Items]
Basis spread on variable rate	2.75%		6%

Long-Term Debt - Aggregate Matu

Long-Term Debt - Aggregate Maturities (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Debt Disclosure [Abstract]
2022	$ 0
2023	450
2024	0
2025	0
2026	1,763,100
Thereafter	0
Total	$ 1,763,550	$ 1,763,550

Income Taxes (Details)

Income Taxes (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Income Tax Disclosure [Abstract]
Effective income tax rate	40.30%	33.20%	36.40%	30.70%

Employee Benefits - Net Periodi

Employee Benefits - Net Periodic Benefit Cost (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	$ 242	$ 300	$ 738	$ 905
Interest cost	1,848	1,622	5,640	4,897
Expected return on plan assets	(3,595)	(3,577)	(10,975)	(10,799)
Amortization of net actuarial loss (gain)	0	269	0	811
Net periodic benefit cost	(1,505)	(1,386)	(4,597)	(4,186)
Other benefits plans
Defined Benefit Plan Disclosure [Line Items]
Service cost	4	7	12	21
Interest cost	63	59	193	179
Amortization of net actuarial loss (gain)	(2)	9	(6)	26
Net periodic benefit cost	$ 65	$ 75	$ 199	$ 226

Employee Benefits - Additional

Employee Benefits - Additional Information (Details) - USD ($) $ in Thousands	9 Months Ended
	Sep. 30, 2022	Dec. 31, 2021
Postemployment Benefits [Abstract]
Expect funding requirements in each of the next five years	$ 3,100
Defined benefit pension plans
Defined Benefit Plan Disclosure [Line Items]
Letters of credit outstanding, amount	$ 45,200	$ 46,200
Defined benefit pension plans | Maximum
Defined Benefit Plan Disclosure [Line Items]
Solvency payment as percent of market value	15%

Other Comprehensive Income (L_3

Other Comprehensive Income (Loss) (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	$ 636,000	$ 523,271	$ 586,096	$ 454,574
Ending balance	606,729	525,769	606,729	525,769
AOCI Attributable to Parent
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(105,014)	(77,468)	(83,566)	(93,842)
Other comprehensive income (loss) before reclassifications	(58,985)	(28,762)	(80,429)	(12,947)
Amounts reclassified from accumulated other comprehensive income (loss)	(2)	278	(6)	837
Net current-period other comprehensive income (loss)	(58,987)	(28,484)	(80,435)	(12,110)
Ending balance	(164,001)	(105,952)	(164,001)	(105,952)
Defined Benefit Plans
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(17,323)	(44,813)	(17,581)	(44,143)
Other comprehensive income (loss) before reclassifications	1,067	1,105	1,329	(124)
Amounts reclassified from accumulated other comprehensive income (loss)	(2)	278	(6)	837
Net current-period other comprehensive income (loss)	1,065	1,383	1,323	713
Ending balance	(16,258)	(43,430)	(16,258)	(43,430)
Foreign Currency Translation
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	(97,452)	(32,655)	(66,389)	(49,699)
Other comprehensive income (loss) before reclassifications	(69,460)	(29,867)	(100,523)	(12,823)
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Net current-period other comprehensive income (loss)	(69,460)	(29,867)	(100,523)	(12,823)
Ending balance	(166,912)	(62,522)	(166,912)	(62,522)
Interest Rate Derivatives
Accumulated Other Comprehensive Income (Loss) [Line Items]
Beginning balance	9,761	0	404	0
Other comprehensive income (loss) before reclassifications	9,408	0	18,765	0
Amounts reclassified from accumulated other comprehensive income (loss)	0	0	0	0
Net current-period other comprehensive income (loss)	9,408	0	18,765	0
Ending balance	$ 19,169	$ 0	$ 19,169	$ 0

Share-Based Compensation - Addi

Share-Based Compensation - Additional Information (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
2020 Omnibus Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Share-based compensation expense	$ 4,100	$ 2,900	$ 13,300	$ 8,500
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	$ 500	700	$ 1,600	2,000
Restricted Stock | Pre-IPO B-1 | Year One
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			20%
Restricted Stock | Pre-IPO B-1 | Year Two
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			20%
Restricted Stock | Pre-IPO B-1 | Year Three
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			20%
Restricted Stock | Pre-IPO B-1 | Year Four
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			20%
Restricted Stock | Pre-IPO B-1 | Year Five
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Vesting percentage			20%
Restricted Stock | Pre-IPO B-2 | Minimum
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Investment, internal rate of return			20%
Cash proceeds to sponsors, ratio to invested capital	250%		250%
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	$ 5,200	3,900
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	$ 2,600	$ 1,600	$ 8,100	$ 4,600

Share-Based Compensation - Pre-

Share-Based Compensation - Pre-IPO Awards (Class B-1 and B-2) (Details) - Restricted Stock	9 Months Ended
	Sep. 30, 2022 shares
Pre-IPO B-1
Number of Shares
Beginning balance (in shares)	1,206,089
Forfeited (in shares)	(32,614)
Vested (in shares)	(345,926)
Ending balance (in shares)	827,549
Pre-IPO B-2
Number of Shares
Beginning balance (in shares)	2,023,959
Forfeited (in shares)	(925,544)
Vested (in shares)	0
Ending balance (in shares)	1,098,415

Share-Based Compensation - Stoc

Share-Based Compensation - Stock Options (Details)	9 Months Ended
	Sep. 30, 2022 $ / shares shares
Number of Shares
Beginning balance (in shares)	2,423,256
Granted (in shares)	1,445,887
Forfeited (in shares)	(454,953)
Exercised (in shares)	0
Ending balance (in shares)	3,414,190
Weighted Average Exercise Price
Beginning balance (in shares) | $ / shares	$ 23.02
Granted (in dollars per share) | $ / shares	19.96
Forfeited (in dollars per share) | $ / shares	22.08
Exercised (in dollars per share) | $ / shares	0
Ending balance (in shares) | $ / shares	$ 21.85
Options vested (in shares)	500,000
Options exercisable (in shares)	500,000

Share-Based Compensation - RSUs

Share-Based Compensation - RSUs (Details) - RSUs	9 Months Ended
	Sep. 30, 2022 $ / shares shares
Number of Shares
Beginning balance (in shares) | shares	640,122
Granted (in shares) | shares	954,685
Forfeited (in shares) | shares	(145,656)
Vested (in shares) | shares	(89,121)
Ending balance (in shares) | shares	1,360,030
Weighted Average Grant Date Fair Value
Beginning balance (in dollars per share) | $ / shares	$ 23.19
Granted (in dollars per share) | $ / shares	20.57
Forfeited (in dollars per share) | $ / shares	21.90
Vested (in dollars per share) | $ / shares	24.13
Ending balance (in dollars per share) | $ / shares	$ 21.43

Earnings Per Share (Details)

Earnings Per Share (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Earnings:
Net income	$ 25,090	$ 27,444	$ 86,149	$ 81,124
Less: Net income attributable to noncontrolling interests	0	0	0	239
Less: Allocation to participating securities	223	343	862	1,089
Less: Allocation to participating securities	223	343	862	1,089
Net income attributable to Sotera Health Company common shareholders	24,867	27,101	85,287	79,796
Net income attributable to Sotera Health Company common shareholders	$ 24,867	$ 27,101	$ 85,287	$ 79,796
Weighted Average Common Shares:
Weighted-average common shares outstanding - basic (in shares)	280,142	279,381	279,988	279,097
Dilutive effect of potential common shares (in shares)	30	179	105	156
Weighted-average common shares outstanding - diluted (in shares)	280,172	279,560	280,093	279,253
Earnings per Common Share:
Net income per common share attributable to Sotera Health Company common shareholders - basic (in dollars per share)	$ 0.09	$ 0.10	$ 0.31	$ 0.29
Net income per common share attributable to Sotera Health Company common shareholders - diluted (in dollars per share)	$ 0.09	$ 0.10	$ 0.31	$ 0.29
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	4,647	2,408	3,433	2,406
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	3,526	2,403	3,399	2,399
RSUs
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Antidilutive securities excluded from computation of earnings per share (in shares)	1,121	5	34	7

Commitments and Contingencies (

Commitments and Contingencies (Details)				9 Months Ended	31 Months Ended
	Sep. 20, 2022 USD ($)	Sep. 19, 2022 USD ($)	Aug. 17, 2020 plaintiff	Sep. 30, 2022 USD ($)	Mar. 31, 2021 plaintiff	Oct. 27, 2022 USD ($)	Oct. 26, 2022 USD ($)	Jun. 28, 2022 segment
Gain Contingencies [Line Items]
Loss contingency, insurance limits per occurrence				$ 10,000,000
Loss contingency, insurance limits				20,000,000
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation
Gain Contingencies [Line Items]
Number of plaintiffs | plaintiff					830
Number of pending claims | segment								4
Amount awarded to other party	$ 358,700,000	$ 358,700,000
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Subsequent Event
Gain Contingencies [Line Items]
Loss contingency, range of possible loss, portion not accrued						$ 358,700,000	$ 0
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Co-defendant
Gain Contingencies [Line Items]
Amount awarded to other party		2,600,000
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Compensatory Damages
Gain Contingencies [Line Items]
Amount awarded to other party		36,100,000
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Punitive Damages Member
Gain Contingencies [Line Items]
Amount awarded to other party		$ 320,000,000
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Scheduled for Trials in 2022
Gain Contingencies [Line Items]
Number of pending claims | segment								2
Ethylene Oxide Tort Litigation - Illinois | Pending Litigation | Scheduled for Trials in 2023
Gain Contingencies [Line Items]
Number of pending claims | segment								2
Ethylene Oxide Tort Litigation – Georgia | Pending Litigation
Gain Contingencies [Line Items]
Number of plaintiffs | plaintiff			300
Loss contingency, utilized limits				$ 7,500,000

Financial Instruments and Fin_3

Financial Instruments and Financial Risk - Additional Information (Details)	3 Months Ended		9 Months Ended
	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Sep. 30, 2022 USD ($)	Sep. 30, 2021 USD ($)	Jun. 30, 2022	May 31, 2022 USD ($) instrument	Dec. 31, 2021 USD ($)	Oct. 31, 2021 USD ($) instrument	Jun. 30, 2021 USD ($)	Feb. 28, 2021 USD ($) instrument	Jun. 30, 2020 USD ($) instrument
Derivative [Line Items]
Derivative loss, net of tax recognized in accumulated other comprehensive income (loss)	$ 9,408,000	$ 0	$ 18,765,000	$ 0
Allowance for uncollectible accounts	1,414,000		1,414,000				$ 1,287,000
Foreign Currency Forward Contracts
Derivative [Line Items]
Fair value of outstanding contracts	0		0				0
Derivatives Designated in Hedge Relationships
Derivative [Line Items]
Derivative loss, net of tax recognized in accumulated other comprehensive income (loss)			22,800,000
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Number of instruments held | instrument						2		2
Notional amount	2,000,000		2,000,000			$ 1,000,000,000	1,000,000	$ 1,000,000,000
Option premium						$ 4,100,000		$ 1,800,000
Percent of borrowing limitation due to cash flow exposure						3.50%		1%
Derivatives Not Designated in Hedge Relationships
Derivative [Line Items]
Notional amount	3,183,600		3,183,600				2,644,400
Derivatives Not Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Number of instruments held | instrument										2
Notional amount	$ 1,000,000		$ 1,000,000				$ 1,500,000			$ 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					1%					0.50%
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 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 ($)	Sep. 30, 2022	May 31, 2022	Dec. 31, 2021	Oct. 31, 2021	Feb. 28, 2021
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Notional Amount	$ 2,000,000	$ 1,000,000,000	$ 1,000,000	$ 1,000,000,000
Fair Value, Derivative Asset	31,920,000		2,322,000
Fair Value, Derivative Liabilities	0		0
Derivatives Not Designated in Hedge Relationships
Derivative [Line Items]
Notional Amount	3,183,600		2,644,400
Fair Value, Derivative Asset	43,194,000		4,472,000
Fair Value, Derivative Liabilities	4,745,000		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
Fair Value, Derivative Asset	7,752,000		1,654,000
Fair Value, Derivative Liabilities	0		0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative
Derivative [Line Items]
Notional Amount	183,600		144,400
Fair Value, Derivative Asset	3,522,000		496,000
Fair Value, Derivative Liabilities	$ 4,745,000		$ 0

Financial Instruments and Fin_5

Financial Instruments and Financial Risk - Activities of Derivative Instruments (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized loss (gain)			$ (4,323)	$ (424)
Unrealized gain on interest rate derivatives recorded in other comprehensive income (loss), net of tax	$ 9,408	$ 0	18,765	0
Interest Rate Cap
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized loss (gain)	3,348	(116)	(6,098)	267
Embedded Derivative
Derivative Instruments, Gain (Loss) [Line Items]
Unrealized loss (gain)	359	1,189	1,776	(424)
Interest Rate Swap
Derivative Instruments, Gain (Loss) [Line Items]
Realized loss (gain)	(4,473)	0	(5,752)	0
Foreign Currency Forward Contracts
Derivative Instruments, Gain (Loss) [Line Items]
Realized loss (gain)	$ 4,157	$ 762	$ 3,662	$ (1,381)

Financial Instruments and Fin_6

Financial Instruments and Financial Risk - Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Sep. 30, 2022	Dec. 31, 2021
Derivatives Designated in Hedge Relationships | Interest Rate Cap
Derivative [Line Items]
Derivative asset	$ 31,920	$ 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	31,920	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	31,920	2,322
Derivatives Not Designated in Hedge Relationships
Derivative [Line Items]
Derivative asset	43,194	4,472
Derivative liabilities	(4,745)	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	1,604,421	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	446	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	56,526	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	7,752	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	7,752	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	3,522	496
Derivative liabilities	(4,745)	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 1
Derivative [Line Items]
Derivative asset	0
Derivative liabilities	0	0
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 2
Derivative [Line Items]
Derivative asset	3,522
Derivative liabilities	4,745	496
Derivatives Not Designated in Hedge Relationships | Embedded Derivative | Fair Value, Level 3
Derivative [Line Items]
Derivative asset	0
Derivative liabilities	0	0
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Term loan, due 2026
Derivative [Line Items]
Long-term debt	1,746,109	1,743,090
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Other long-term debt
Derivative [Line Items]
Long-term debt	446	444
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Finance Lease Obligations (with current portion)
Derivative [Line Items]
Long-term debt	56,526	42,047
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Interest Rate Cap
Derivative [Line Items]
Derivative asset	7,752	1,654
Derivatives Not Designated in Hedge Relationships | Carrying Amount | Embedded Derivative
Derivative [Line Items]
Derivative asset	3,522
Derivative liabilities	$ 4,745	$ 496

Segment Information - Additiona

Segment Information - Additional Information (Details) - segment	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting [Abstract]
Number of reportable segments			3
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer One
Segment Reporting Information [Line Items]
Percentage	21%	20.40%	17.10%	13.20%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Two
Segment Reporting Information [Line Items]
Percentage	14.70%	12.80%	16.20%	12.80%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Three
Segment Reporting Information [Line Items]
Percentage	10.10%	12.80%	11.80%	12.60%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Four
Segment Reporting Information [Line Items]
Percentage		10.30%	11.70%	12.30%
Operating Segments | Nordion | Revenue from Contract with Customer Benchmark | Customer Concentration Risk | Customer Five
Segment Reporting Information [Line Items]
Percentage				10.50%

Segment Information - Segment O

Segment Information - Segment Operating Results (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Net revenues	$ 248,704	$ 226,164	$ 752,097	$ 690,229
Total capital expenditures			110,642	60,898
Sterigenics
Segment Reporting Information [Line Items]
Net revenues	157,723	145,314	464,977	421,647
Total capital expenditures			90,444	48,552
Nordion
Segment Reporting Information [Line Items]
Net revenues	35,071	28,768	119,551	103,811
Total capital expenditures			12,045	7,531
Nelson Labs
Segment Reporting Information [Line Items]
Net revenues	55,910	52,082	167,569	164,771
Total capital expenditures			8,153	4,815
Operating Segments
Segment Reporting Information [Line Items]
Net revenues	248,704	226,164	752,097	690,229
Segment income	125,152	116,674	376,636	356,554
Operating Segments | Sterigenics
Segment Reporting Information [Line Items]
Net revenues	157,723	145,314	464,977	421,647
Segment income	85,587	79,344	250,088	227,374
Operating Segments | Nordion
Segment Reporting Information [Line Items]
Net revenues	35,071	28,768	119,551	103,811
Segment income	20,294	16,331	69,179	61,285
Operating Segments | Nelson Labs
Segment Reporting Information [Line Items]
Net revenues	55,910	52,082	167,569	164,771
Segment income	19,271	20,999	57,369	67,895
Intersegment
Segment Reporting Information [Line Items]
Net revenues	$ (7,400)	$ (3,700)	$ (38,700)	$ (21,200)

Segment Information - Reconcili

Segment Information - Reconciliation of Reportable Segment Amounts (Details) - USD ($) $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Segment Reporting Information [Line Items]
Share-based compensation			$ 14,955	$ 10,489
Impairment of investment in unconsolidated affiliate	$ 0	$ 0	9,613	0
Loss on extinguishment of debt	0	6,365	0	20,677
Accretion of asset retirement obligation			1,645	1,751
Net income attributable to Sotera Health Company	25,090	27,444	86,149	80,885
Interest Rate Cap | Interest Expense, Net
Segment Reporting Information [Line Items]
Unrealized loss (gain)	3,300		(6,100)
Nordion
Segment Reporting Information [Line Items]
Gain on business interruption insurance recovery			3,400
Operating Segments
Segment Reporting Information [Line Items]
Segment income	125,152	116,674	376,636	356,554
Operating Segments | Nordion
Segment Reporting Information [Line Items]
Segment income	20,294	16,331	69,179	61,285
Segment Reconciling Items
Segment Reporting Information [Line Items]
Interest expense, net	20,080	18,140	53,974	58,585
Depreciation and amortization	36,104	37,634	109,092	112,756
Share-based compensation	4,616	3,547	14,955	10,489
Gain on foreign currency and derivatives not designated as hedging instruments, net	3,194	1,881	(4,788)	885
Acquisition and divestiture related charges, net	447	(2,662)	978	(2,003)
Business optimization project expenses	1,035	244	1,609	780
Plant closure expenses	2,627	266	3,776	1,564
Loss on extinguishment of debt	0	6,365	0	20,677
Professional services relating to EO sterilization facilities	14,501	9,449	50,238	33,492
Accretion of asset retirement obligation	526	598	1,644	1,751
COVID-19 expenses	6	109	154	596
Net income attributable to Sotera Health Company	$ 42,016	$ 41,103	$ 135,391	$ 116,982