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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Guarantor obligation percentage of exposure in case of default.

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Interest rate per year in excess of Euribor as of date of the note.

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The number of sheet processing facilities operated by equity method investment.

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Period used for lag basis.

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Step-up to fair value of equity method investment, portion related to identification of goodwill.

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The aggregate amount of recurring noncash expense charged against earnings in the period to allocate the cost of assets over their estimated remaining economic lives.

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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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Difference between amount at which an investment accounted for under the equity method of accounting is carried (reported) on the balance sheet and amount of underlying equity in net assets the reporting Entity has in the investee.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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This item represents the entity's ownership percentage in the investee multiplied by the investee's total equity.

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This item represents the carrying amount on the entity's balance sheet of its investment in common stock of an equity method investee. This is not an indicator of the fair value of the investment, rather it is the initial cost adjusted for the entity's share of earnings and losses of the investee, adjusted for any distributions (dividends) and other than temporary impairment (OTTI) losses recognized.

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

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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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Date of maturity or expiration of arrangements with a related party (for example, but not limited to, leasing and debt arrangements between related parties), in CCYY-MM-DD format.

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Identify the stated interest rate per the agreement, for example, leasing and debt arrangements between related parties.

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No definition available.

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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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Equity Investments - Additional Information (Detail) $ in Thousands, € in Millions	12 Months Ended
	Dec. 31, 2018 USD ($) Sheet	Dec. 31, 2017 USD ($)	Dec. 31, 2016 USD ($)	Dec. 31, 2018 EUR (€)	Dec. 31, 2017 EUR (€)
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ 869,900	$ 750,100
Distributions from affiliates	30,196	49,295	$ 40,602
Amortization expense due to fair value step-up	88,758	91,228	73,862
NuMit LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ 337,200	321,400
Equity method investment, ownership percentage	50.00%			50.00%
Period used for lag basis, in months	1 month
Distributions from affiliates	$ 29,200	48,300	38,600
Steel Technologies LLC [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment, ownership percentage	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 investment	$ 269,100	285,900
Equity method investment, ownership percentage	50.00%			50.00%
Period used for lag basis, in months	1 month
Equity method investments, share of net assets	$ 113,500
Basis difference due to the step-up to fair value of certain assets and liabilities	155,600
Step-up to fair value of equity method investment, portion related to identification of goodwill	88,500
Amortization expense due to fair value step-up	9,300	8,900	$ 8,800
Due from related parties, noncurrent	$ 40,200	41,900		€ 35.0	€ 35.0
Notes receivable, related parties, interest rate	0.84%
Interest rate per year in excess of Euribor as of date of the notes	1.00%
Equity method investments notes payable with parent company, maturity date	Jan. 31, 2022
Nucor JFE [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investment	$ 135,700	71,100
Equity method investment, ownership percentage	50.00%			50.00%
Period used for lag basis, in months	1 month
Facility A [Member] \| Duferdofin Nucor S.r.l. [Member]
Schedule of Equity Method Investments [Line Items]
Equity method investments credit facilities, amount	$ 183,700			€ 160.0
Total amount outstanding under equity method investments credit facilities	$ 178,000	$ 146,700		€ 155.0	€ 122.5
Guarantor obligation percentage of exposure in case of default	50.00%			50.00%
Line of credit facility, maturity period	Apr. 16, 2021