The subsidiary's percentage of ownership of common stock or equity participation in a company.

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Total amount outstanding under equity method investments applicable credit facilities.

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The equity method investments available credit facilities subject to guarantee.

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Equity method investments principal amount subject to guarantee for other credit facilities.

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Guarantor obligation percentage of exposure in case of default.

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Charges related to impairments, losses or cumulative foreign currency translation losses reclassified into earnings related to certain assets.

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Number of sheet processing facilities operated by equity investment.

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Percentage of interest held by other party in other entity.

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Period used for lag basis.

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Aggregate amount of receivables to be collected from related parties where one party can exercise control or significant influence over another party; including affiliates, owners or officers and their immediate families, pension trusts, and so forth, at the financial statement date. which are usually due after one year (or one business cycle).

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The cash inflow from an entity that is affiliated with the entity by means of direct or indirect ownership.

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Equity Investments - Additional Information (Detail) € in Millions	3 Months Ended				12 Months Ended
	Dec. 31, 2020 USD ($)	Oct. 03, 2020 USD ($)	Jul. 04, 2020 USD ($)	Apr. 04, 2020 USD ($)	Dec. 31, 2020 USD ($) Sheet	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2020 EUR (€)	Dec. 15, 2020 USD ($)	Dec. 31, 2019 EUR (€)	Jan. 16, 2019
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 520,000,000.0				$ 520,000,000.0	$ 793,200,000
Equity method investments impairment charges					613,640,000	66,916,000	$ 110,000,000
NuMit LLC [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 323,600,000				$ 323,600,000	319,800,000
Equity method investment, ownership percentage	50.00%				50.00%			50.00%
Period used for lag basis, in months					1 month
Distributions from affiliates					$ 9,500,000	36,500,000	$ 29,200,000
Steel Technologies LLC [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	100.00%				100.00%			100.00%
Number of sheet processing facilities operated by Steel Technologies \| Sheet					26
Duferdofin Nucor S.r.l. [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 0				$ 0	263,000,000.0
Equity method investment, ownership percentage	50.00%				50.00%			50.00%
Period used for lag basis, in months					1 month
Percentage of interest held by other party in other entity	100.00%				100.00%			100.00%
Due from related parties, noncurrent	$ 37,800,000				$ 37,800,000	39,300,000		€ 35.0		€ 35.0
Equity method investments impairment charges	25,400,000	$ 6,600,000	$ 5,000,000.0	$ 250,000,000.0
Cumulative foreign currency translation losses reclassified into earnings	158,600,000
Equity method investments impairment charges	184,000,000.0			$ 287,800,000	483,500,000
Nucor-JFE [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments	$ 147,100,000				$ 147,100,000	163,200,000
Equity method investment, ownership percentage	50.00%				50.00%			50.00%			50.00%
Principal amount subject to guarantee for other credit facilities	$ 25,000,000.0				$ 25,000,000.0	25,000,000.0
Nucor-JFE [Member] \| General Financing Agreement and Promissory Note [Member]
Schedule Of Equity Method Investments [Line Items]
Equity method investments credit facilities subject to guarantee, amount									$ 90,000,000.0
Total amount outstanding under equity method investments credit facilities	$ 50,000,000.0				$ 50,000,000.0	$ 0
Guarantor obligation percentage of exposure in case of default	50.00%				50.00%			50.00%