Derivative inception period.

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- Definition

Derivative maturity period.

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No definition available.

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- Definition

Interest rate on overdue amounts and during default.

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No definition available.

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- Definition

Line of credit facility commitment fee percentage increase (decrease).

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No definition available.

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- Definition

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

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No definition available.

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Incremental percentage increase (decrease) in the stated rate on a debt instrument.

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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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No definition available.

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- Definition

Weighted average interest rate of debt outstanding.

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No definition available.

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- Definition

Amount of hedged item in hedging relationship. Excludes hedged asset or liability.

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No definition available.

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- Definition

Fixed interest rate related to the interest rate derivative.

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No definition available.

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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.

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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

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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).

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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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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.

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

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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.

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

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The carrying value as of the balance sheet date of the current portion 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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Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
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-SubTopic 210
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Long-Term Debt - Ryerson Credit Facility - Additional Information (Detail) - USD ($)			1 Months Ended			3 Months Ended
	Sep. 23, 2019	Nov. 16, 2016	Nov. 30, 2019	Jun. 30, 2019	Mar. 31, 2017	Mar. 31, 2020	Dec. 31, 2019	Jun. 28, 2018
Ryerson Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity						$ 1,000,000,000		$ 1,000,000,000.0
Credit facility maturity date						Nov. 16, 2021
Reduction in interest rate on outstanding borrowing		0.25%
Reduction in commitment fees on amounts not borrowed		0.025%
Outstanding borrowings						$ 546,300,000	$ 377,700,000
Letters of credit						11,000,000	11,000,000
Available credit facility						$ 159,000,000	$ 348,000,000
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 (and in the case of Canadian accounts, the Canadian 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 (and in the case of Canadian accounts, the Canadian borrower). Qualified cash consists of cash in an eligible deposit account that is subject to customary restrictions and liens in favor of the lenders
Default bear interest rate						2.00%
Commitment fees on amounts not borrowed						0.23%
Ryerson Credit Facility [Member] \| Interest Rate Swap [Member]
Debt Instrument [Line Items]
Interest rate swap agreement date					2017-03
Hedged debt amount					$ 150,000,000
Derivative fixed interest rate			1.539%		1.658%
Derivative maturity period					2020-03
Ryerson Credit Facility [Member] \| Second Interest Rate Swap [Member]
Debt Instrument [Line Items]
Interest rate swap agreement date				2019-06
Hedged debt amount				$ 60,000,000
Derivative fixed interest rate				1.729%
Derivative maturity period				2022-06
Ryerson Credit Facility [Member] \| Third Interest Rate Swap [Member]
Debt Instrument [Line Items]
Interest rate swap agreement date			2019-11
Hedged debt amount			$ 100,000,000
Derivative fixed interest rate			1.539%
Derivative maturity period			2022-11
Ryerson Credit Facility [Member] \| All Interest Rate Swap [Member]
Debt Instrument [Line Items]
Weighted average interest rate						2.40%	3.20%
Ryerson Credit Facility [Member] \| Federal Funds Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						0.50%
Ryerson Credit Facility [Member] \| Prime Rate and One Month LIBOR Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.00%
Ryerson Credit Facility [Member] \| 30 Day LIBOR Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.00%
Ryerson Credit Facility [Member] \| One Month Canadian Bankers Acceptance Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.00%
Ryerson Credit Facility [Member] \| US Subsidiaries [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity						$ 940,000,000
Ryerson Credit Facility [Member] \| Canadian Subsidiaries [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity						$ 60,000,000
Ryerson Credit Facility [Member] \| Canadian Subsidiaries [Member] \| Federal Funds Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						0.50%
Ryerson Credit Facility [Member] \| Minimum [Member] \| Base Rate and Canadian Prime Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						0.25%
Ryerson Credit Facility [Member] \| Minimum [Member] \| LIBOR and Banker's Acceptance Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.25%
Ryerson Credit Facility [Member] \| Maximum [Member] \| Base Rate and Canadian Prime Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						0.50%
Ryerson Credit Facility [Member] \| Maximum [Member] \| LIBOR and Banker's Acceptance Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.50%
Old Revolving Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity		$ 1,000,000,000.0
Amended Old Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity		$ 750,000,000
FILO Facility [Member] \| Ryerson Credit Facility [Member]
Debt Instrument [Line Items]
Revolving credit facility maximum borrowing capacity	$ 67,900,000
Credit facility maturity date	Jun. 30, 2020
Outstanding borrowings						$ 16,900,000	$ 34,300,000
FILO Facility [Member] \| Ryerson Credit Facility [Member] \| Minimum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.25%
FILO Facility [Member] \| Ryerson Credit Facility [Member] \| Minimum [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Spread over base interest rate						2.25%
FILO Facility [Member] \| Ryerson Credit Facility [Member] \| Maximum [Member] \| Base Rate [Member]
Debt Instrument [Line Items]
Spread over base interest rate						1.50%
FILO Facility [Member] \| Ryerson Credit Facility [Member] \| Maximum [Member] \| LIBOR [Member]
Debt Instrument [Line Items]
Spread over base interest rate						2.50%