Consolidated Statements of Earnings (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended
Apr. 04, 2015	Apr. 05, 2014
Income Statement [Abstract]
Net sales	$ 4,399,440us-gaap_SalesRevenueNet	$ 5,108,444us-gaap_SalesRevenueNet
Costs, expenses and other:
Cost of products sold	4,111,158us-gaap_CostOfGoodsSold	4,731,242us-gaap_CostOfGoodsSold
Marketing, administrative and other expenses	124,561	133,434
Equity in losses (earnings) of unconsolidated affiliates	259	(4,474)
Interest expense, net	44,417us-gaap_InterestRevenueExpenseNet	40,741us-gaap_InterestRevenueExpenseNet
Costs, expenses and other, total	4,280,395	4,900,943
Earnings before income taxes and noncontrolling interests	119,045	207,501
Provision for income taxes	34,753us-gaap_IncomeTaxExpenseBenefit	77,805us-gaap_IncomeTaxExpenseBenefit
Net earnings	84,292us-gaap_ProfitLoss	129,696us-gaap_ProfitLoss
Earnings attributable to noncontrolling interests	16,492	18,665
Net earnings attributable to Nucor stockholders	$ 67,800us-gaap_NetIncomeLoss	$ 111,031us-gaap_NetIncomeLoss
Net earnings per share:
Basic	$ 0.21us-gaap_EarningsPerShareBasic	$ 0.35us-gaap_EarningsPerShareBasic
Diluted	$ 0.21us-gaap_EarningsPerShareDiluted	$ 0.35us-gaap_EarningsPerShareDiluted
Average shares outstanding:
Basic	320,315	319,505
Diluted	320,483	319,768
Dividends declared per share	$ 0.3725	$ 0.3700

The sum of operating and non-operating costs and expenses.

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Aggregate dividends declared during the period for each share of common stock outstanding.

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Total costs related to goods produced and sold during the reporting period.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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The amount of net income (loss) for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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This element represents the income or loss from continuing operations attributable to the economic entity which may also be defined as revenue less expenses from ongoing operations, after income or loss from equity method investments, but before income taxes, extraordinary items, and noncontrolling interest.

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This item represents the entity's proportionate share for the period of the net income (loss) of its investee (such as unconsolidated subsidiaries and joint ventures) to which the equity method of accounting is applied. This item includes income or expense related to stock-based compensation based on the investor's grant of stock to employees of an equity method investee.

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Amount of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

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Amount of interest revenue (income derived from investments in debt securities and on cash and cash equivalents) net of interest expense (cost of borrowed funds accounted for as interest).

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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Amount of Net Income (Loss) attributable to noncontrolling interest.

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The consolidated profit or loss for the period, net of income taxes, including the portion attributable to the noncontrolling interest.

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Total revenue from sale of goods and services rendered during the reporting period, in the normal course of business, reduced by sales returns and allowances, and sales discounts.

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The aggregate total costs related to selling a firm's product and services, as well as all other general and administrative expenses. Direct selling expenses (for example, credit, warranty, and advertising) are expenses that can be directly linked to the sale of specific products. Indirect selling expenses are expenses that cannot be directly linked to the sale of specific products, for example telephone expenses, Internet, and postal charges. General and administrative expenses include salaries of non-sales personnel, rent, utilities, communication, etc.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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