Fair value, after effects of master netting arrangements, of financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset offset against the right to receive collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

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- Definition

Fixed interest rate related to the interest rate derivative.

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- Definition

Nominal or face amount used to calculate payment on derivative.

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The number of derivative instruments of a particular group held by the entity.

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Period the derivative contract is outstanding, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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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

Fair value as of the balance sheet date of all interest rate derivatives designated as cash flow hedging instruments.

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The estimated net amount of unrealized gains or losses on interest rate cash flow hedges as of the balance sheet date expected to be reclassified to earnings within the next twelve months.

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Derivatives and Fair Value Measurements - Additional Information (Detail) $ in Millions	3 Months Ended
	Mar. 31, 2020 USD ($) DerivativeInstrument	Dec. 31, 2019 USD ($)	Nov. 30, 2019 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2017
Derivatives Fair Value [Line Items]
Fair value of interest rate swaps	$ 4.9
Derivative liabilities, offset against cash collateral	$ 0.5	$ 2.7
Minimum [Member]
Derivatives Fair Value [Line Items]
General term for commodity and exchange contracts	1 month
Maximum [Member]
Derivatives Fair Value [Line Items]
General term for commodity and exchange contracts	12 months
Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Derivative notional amount	$ 160.0	$ 310.0
Derivative gain (loss) to be reclassified into interest income during next 12 months	$ 1.8
Ryerson Credit Facility [Member]
Derivatives Fair Value [Line Items]
Number of derivative instruments \| DerivativeInstrument	2
Ryerson Credit Facility [Member] \| Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Derivative notional amount			$ 100.0
Derivative fixed interest rate			1.539%		1.658%
Ryerson Credit Facility [Member] \| Second Interest Rate Swaps [Member]
Derivatives Fair Value [Line Items]
Derivative notional amount				$ 60.0
Derivative fixed interest rate				1.729%