Debt instrument basis spread leverage ratio.

No definition available.

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Balance Type:	na
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- Definition

Debt instrument basis spread reduction rate.

+ References

No definition available.

+ Details

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- Definition

FILO facility expiration period.

+ References

No definition available.

+ Details

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- Definition

Interest rate on overdue amounts and during default.

+ 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.

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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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+ Details

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- Definition

Weighted average interest rate of debt outstanding.

+ References

No definition available.

+ Details

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

+ References

No definition available.

+ Details

Name:	us-gaap_LettersOfCreditOutstandingAmount
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Balance Type:	credit
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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.

+ References

+ Details

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Balance Type:	credit
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- Definition

Discussion of whether the borrowings under the credit facility are secured or unsecured and, if secured, a description of collateral (for example, accounts receivable less than 120 days old, finished goods inventory).

+ References

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- Definition

The fee, expressed as a percentage of the line of credit facility, for the line of credit facility regardless of whether the facility has been used.

+ References

No definition available.

+ Details

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- Definition

Amount of current borrowing capacity under the credit facility considering any current restrictions on the amount that could be borrowed (for example, borrowings may be limited by the amount of current assets), but without considering any amounts currently outstanding under the facility.

+ References

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Balance Type:	credit
Period Type:	instant

- Definition

Date the credit facility terminates, in YYYY-MM-DD format.

+ 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

Amount of borrowing capacity currently available under the credit facility (current borrowing capacity less the amount of borrowings outstanding).

+ References

+ Details

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Long-Term Debt - Ryerson Credit Facility - Additional Information (Detail) - USD ($) $ in Millions		3 Months Ended
	Jun. 29, 2022	Mar. 31, 2024	Dec. 31, 2023	Jun. 28, 2022
Ryerson Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity	$ 1,300.0			$ 1,000.0
Credit facility maturity date	Jun. 29, 2027
Outstanding borrowings		$ 498.0	$ 433.0
Letters of credit		8.0	10.0
Available credit facility		$ 597.0	$ 560.0
Line of credit facility, description of collateral		Total credit availability is limited by the amount of eligible accounts receivable, inventory, and qualified cash pledged as collateral under the agreement insofar as Ryerson is subject to a borrowing base comprised of the aggregate of these three amounts, less applicable reserves. Eligible accounts receivable, at any date of determination, is comprised of the aggregate value of all accounts directly created by a borrower in the ordinary course of business arising out of the sale of goods or the rendering of services, each of which has been invoiced, with such receivables adjusted to exclude various ineligible accounts, including, among other things, those to which a borrower (or guarantor, as applicable) does not have sole and absolute title and accounts arising out of a sale to an employee, officer, director, or affiliate of a borrower (or guarantor, as applicable). Eligible inventory, at any date of determination, is comprised of the net orderly liquidation value of all inventory owned by a borrower. Qualified cash consists of cash in an eligible deposit account that is subject to customary restrictions and liens in favor of the lenders.
Debt instrument basis spread reduction rate		0.125%
Debt instrument basis spread leverage ratio		3.5
Default bear interest rate		2.00%
Commitment fees on amounts not borrowed		0.20%
Weighted average interest rate		6.50%	6.60%
Ryerson Credit Facility [Member] \| US Borrower [Member] \| Federal Funds Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		0.50%
Ryerson Credit Facility [Member] \| US Borrower [Member] \| Term SOFR Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		1.00%
Ryerson Credit Facility [Member] \| US Borrower [Member] \| Prime Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		0.50%
Ryerson Credit Facility [Member] \| Canadian Borrower [Member] \| Term SOFR Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		1.00%
Ryerson Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		0.25%
Ryerson Credit Facility [Member] \| Minimum [Member] \| S O F R and C D O R Rates [Member]
Debt Instrument [Line Items]
Spread over base interest rate		1.25%
Ryerson Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate		0.50%
Ryerson Credit Facility [Member] \| Maximum [Member] \| S O F R and C D O R Rates [Member]
Debt Instrument [Line Items]
Spread over base interest rate		1.50%
Old Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Credit facility maturity date	Nov. 05, 2025
First In Last Out Subfacility \| Ryerson Credit Facility [Member]
Debt Instrument [Line Items]
Amount available to be borrowed under FILO Facility	$ 100.0
FILO facility expiration	2 years