Debt Instrument, Notice Period Required For Redemption

No definition available.

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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.

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

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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.

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- Definition

Percentage price of original principal amount of debt at which debt can be redeemed by the issuer.

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- Definition

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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- Definition

Amount of contribution received by defined benefit plan from employer which increases plan assets.

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- Definition

The cash inflow from additional borrowings, net of cash paid to third parties in connection with debt origination.

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Debt - 2030 Notes - Narrative (Details) - USD ($) $ in Millions	1 Months Ended	12 Months Ended
	Aug. 31, 2023	Dec. 28, 2025	Dec. 29, 2024
Debt Instrument [Line Items]
Debt issuance costs, net		$ 11.6	$ 14.2
Pension Benefits
Debt Instrument [Line Items]
Pension plan contributions	$ 222.0	5.1	3.3
ATI Inc. 7.25% Senior Notes due 2030 \| Notes
Debt Instrument [Line Items]
Debt instrument carrying amount	$ 425.0	$ 425.0	$ 425.0
Interest rate	7.25%	7.25%
Proceeds from debt, net of issuance costs	$ 418.8
Debt issuance costs, net	$ 6.2
Debt instrument, term	7 years
Debt instrument, redemption price, percentage	101.00%
ATI Inc. 7.25% Senior Notes due 2030 \| Minimum \| Notes
Debt Instrument [Line Items]
Debt instrument, notice period required for redemption	15 days
ATI Inc. 7.25% Senior Notes due 2030 \| Maximum \| Notes
Debt Instrument [Line Items]
Debt instrument, notice period required for redemption	60 days