Employee retention credits

No definition available.

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- Definition

Employee Retention Credits, Aviation Manufacturing Jobs Protection Program

+ References

No definition available.

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- Definition

Income From Government Assistance, CARES Act

+ References

No definition available.

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- Definition

Other Nonoperating Income (Expense), Litigation Reserve

+ References

No definition available.

+ Details

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
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- Definition

Amount before tax of gain (loss) recognized on the sale or disposal of a disposal group. Excludes discontinued operations.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
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- Definition

Amount of gain (loss) on sale or disposal of other assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
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- Definition

Amount of gain (loss) from the difference between the sale price or salvage price and the book value of an asset that was sold or retired, and gain (loss) from the write down of assets from their carrying value to fair value.

+ References

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- Definition

Number of operating segments. An operating segment is a component of an enterprise: (a) that engages in business activities from which it may earn revenues and incur expenses (including revenues and expenses relating to transactions with other components of the same enterprise), (b) whose operating results are regularly reviewed by the enterprise's chief operating decision maker to make decisions about resources to be allocated to the segment and assess its performance, and (c) for which discrete financial information is available. An operating segment may engage in business activities for which it has yet to earn revenues, for example, start-up operations may be operating segments before earning revenues.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 280
-SubTopic 10
-Section 50
-Paragraph 18
-URI https://asc.fasb.org/extlink&oid=126901519&loc=d3e8672-108599

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- Definition

Amount of expenses associated with exit or disposal activities pursuant to an authorized plan. Excludes expenses related to a discontinued operation or an asset retirement obligation.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 420
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-URI https://asc.fasb.org/extlink&oid=115931487&loc=d3e140904-122747

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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Business Segments - Additional Information (Details)	3 Months Ended
Business Segments - Additional Information (Details)	Mar. 31, 2023 USD ($) segment	Mar. 31, 2022 USD ($)	Dec. 31, 2022 USD ($)
Restructuring Cost and Reserve [Line Items]
Number of business segments \| segment	2
Government sponsored COVID relief income		$ 29,000,000
Gain (Loss) on sale of business	$ 0	(18,300,000)
Litigation Reserve	0	8,600,000
Restructuring charges (credits)	0	(1,100,000)
Gain (loss) on asset sales and sale of businesses, net	0	(18,300,000)
ATI Inc. 3.5% Convertible Senior Notes due 2025 \| Convertible Debt
Restructuring Cost and Reserve [Line Items]
Debt, Gross	$ 291,400,000		$ 291,400,000
Sheffield, UK Operations
Restructuring Cost and Reserve [Line Items]
Gain (Loss) on sale of business		(25,100,000)
Pico Rivera, CA Operations
Restructuring Cost and Reserve [Line Items]
Gain (Loss) on sale of assets		6,800,000
High Performance Materials & Components
Restructuring Cost and Reserve [Line Items]
Employee retention credits and Aviation Manufacturing Jobs Protection Program		22,000,000
Advanced Alloys & Solutions
Restructuring Cost and Reserve [Line Items]
Employee retention credits		$ 7,000,000