Debt Covenant, Undrawn Availability Requirement, Amount

No definition available.

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- Definition

Debt Covenant, Undrawn Availability Requirement, Percent Of Total Available Liquidity

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Fixed Charge Coverage Ratio

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Fixed Coverage Ratio Restriction, Minimum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Fixed Coverage Ratio Restriction, Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Fixed Coverage Ratio Restriction, Percent Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Covenant, Minimum Liquidity, Number of Days Prior

+ References

No definition available.

+ Details

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- Definition

Debt Instrument, Prepayment Increments, Minimum

+ References

No definition available.

+ Details

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- Definition

Line of Credit Facility, Increase to Maximum Borrowing Capacity

+ References

No definition available.

+ Details

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- Definition

Percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ 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

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- Definition

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

+ References

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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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- Definition

Nominal or face amount used to calculate payment on derivative.

+ References

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- Definition

The carrying value as of the balance sheet date of the current and noncurrent portions of long-term obligations drawn from a line of credit, which is a bank's commitment to make loans up to a specific amount. Examples of items that might be included in the application of this element may consist of letters of credit, standby letters of credit, and revolving credit arrangements, under which borrowings can be made up to a maximum amount as of any point in time conditional on satisfaction of specified terms before, as of and after the date of drawdowns on the line. Includes short-term obligations that would normally be classified as current liabilities but for which (a) postbalance sheet date issuance of a long term obligation to refinance the short term obligation on a long term basis, or (b) the enterprise has entered into a financing agreement that clearly permits the enterprise to refinance the short-term obligation on a long term basis and the following conditions are met (1) the agreement does not expire within 1 year and is not cancelable by the lender except for violation of an objectively determinable provision, (2) no violation exists at the BS date, and (3) the lender has entered into the financing agreement is expected to be financially capable of honoring the agreement.

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- Definition

Average amount borrowed under the credit facility during the period.

+ References

No definition available.

+ Details

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- Definition

The effective interest rate during the reporting period.

+ References

+ Details

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- Definition

Maximum borrowing capacity under the credit facility without consideration of any current restrictions on the amount that could be borrowed or the amounts currently outstanding under the facility.

+ References

+ Details

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- Definition

Reflects the total carrying amount as of the balance sheet date of debt having initial terms less than one year or the normal operating cycle, if longer.

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Debt - Revolving Credit Facility Narrative (Details) - USD ($)	6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Sep. 30, 2024	Dec. 31, 2020	Feb. 15, 2016	Dec. 31, 2013
Allegheny Technologies 5.875% Notes due 2023 (a)
Debt Instrument [Line Items]
Outstanding borrowings	$ 500,000,000.0			$ 500,000,000.0
Interest rate	7.875%			7.875%	7.875%	5.875%
Domestic Bank Group $500 million asset-based credit facility
Debt Instrument [Line Items]
Amount utilized to support the issuance of letters of credit	$ 42,800,000
Average borrowings during period	0	$ 58,000,000
Interest rate during period		2.20%
Short-term Debt	0			$ 0
Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 500,000,000
Minimum fixed charge coverage ratio allowed in event of default	1.00
Borrowing capacity unavailable due to fixed charge coverage ratio covenant, maximum	$ 87,500,000
Percentage of borrowing capacity unavailable due to fixed charge coverage ratio covenant	12.50%
Borrowing capacity unavailable due to fixed charge coverage ratio covenant, minimum	$ 62,500,000
Minimum required liquidity number of days prior to maturity of Senior Notes	90 days
Debt covenant, undrawn availability requirement, amount	$ 150,000,000
Debt covenant, undrawn availability requirement, percent of total available liquidity	30.00%
Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility \| Minimum \| LIBOR based borrowings
Debt Instrument [Line Items]
Variable interest rate (percentage)	1.25%
Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility \| Minimum \| Base rate borrowings
Debt Instrument [Line Items]
Variable interest rate (percentage)	0.25%
Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility \| Maximum \| LIBOR based borrowings
Debt Instrument [Line Items]
Variable interest rate (percentage)	1.75%
Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility \| Maximum \| Base rate borrowings
Debt Instrument [Line Items]
Variable interest rate (percentage)	0.75%
Domestic Bank Group $500 million asset-based credit facility \| Letter of credit sub-facility
Debt Instrument [Line Items]
Maximum borrowing capacity	$ 200,000,000
2024 Term Loan
Debt Instrument [Line Items]
Outstanding borrowings	200,000,000			200,000,000.0
Minimum prepayment increments allowed	$ 25,000,000
Interest rate	4.21%
2024 Term Loan \| Interest Rate Swap
Debt Instrument [Line Items]
Notional amount of derivative	$ 50,000,000
2024 Term Loan \| LIBOR based borrowings
Debt Instrument [Line Items]
Variable interest rate (percentage)	2.00%
Allegheny Technologies 4.75% Convertible Senior Notes due 2022
Debt Instrument [Line Items]
Outstanding borrowings	$ 84,200,000			$ 84,200,000
Interest rate	4.75%			4.75%
Forecast \| Domestic Bank Group $500 million asset-based credit facility \| Revolving credit facility
Debt Instrument [Line Items]
Line of credit facility, increase to maximum borrowing capacity			$ 200,000,000