Debt instrument redemption amount outstanding.

No definition available.

Name:	ryi_DebtInstrumentRedemptionAmountOutstanding
Namespace Prefix:	ryi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Gains losses on retirement of debt.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Principal amount for partial redemption.

+ References

No definition available.

+ Details

Name:	ryi_PrincipalAmountForPartialRedemption
Namespace Prefix:	ryi_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Face (par) amount of debt instrument at time of issuance.

+ References

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+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

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

+ References

+ Details

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Data Type:	dtr-types:percentItemType
Balance Type:	na
Period Type:	instant

- 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

Face (par) amount of the original debt instrument that was repurchased.

+ References

No definition available.

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

The cash outflow for the extinguishment of long-term borrowing, with the highest claim on the assets of the entity in case of bankruptcy or liquidation, before its maturity.

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- Definition

Fair value as of the balance sheet date of the embedded derivative or group of embedded derivatives classified as an asset.

+ References

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- Definition

Net Increase or Decrease in the fair value of the embedded derivative or group of embedded derivatives included in earnings in the period.

+ References

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- Definition

Write-off of amounts previously capitalized as debt issuance cost in an extinguishment of debt.

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Long-Term Debt - 2028 Notes - Additional Information (Detail) - 2028 Notes [Member] - USD ($) $ in Millions	3 Months Ended	6 Months Ended	12 Months Ended
	Jun. 30, 2022	Jun. 30, 2022	Dec. 31, 2021	Jul. 22, 2020
Debt Instrument [Line Items]
Debt Instrument, Face Amount				$ 500.0
Debt Instrument Interest Rate Stated Percentage				8.50%
Principal Amount For Partial Redemption			$ 200.0
Debt principal amount remained outstanding	$ 50.0	$ 50.0	300.0
2028 Notes Embedded Derivative Fair Value	0.0	0.0	$ 0.2
Change in embedded derivative fair value		0.2
Principal amount of debt instrument repurchased	250.0	250.0
Cash outflow to retire debt		267.7
Tender Offer [Member]
Debt Instrument [Line Items]
Principal amount of debt instrument repurchased	132.2	132.2
Cash outflow to retire debt	140.8
Gain (loss) on retirement of debt	(10.7)
Debt issuance cost written off	$ 2.1
Other Income and (Expense), Net [Member]
Debt Instrument [Line Items]
Gain (loss) on retirement of debt		(19.8)
Interest Expense [Member]
Debt Instrument [Line Items]
Debt issuance cost written off		$ 1.9