Amortization expense and other purchase accounting adjustments associated with the fair value step-up.

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Debt instrument maturity date.

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Total amount outstanding under equity method investment's applicable credit facilities.

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The equity method investment's available credit facilities subject to guarantee.

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The portion of the equity investment's outstanding balance under its credit facilities that is guaranteed by Nucor.

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Interest rate on line of credit to related party in excess of LIBOR.

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The interest rate on the note to related party in excess of LIBOR.

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

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Interest rate per year that was reset in excess of Euribor rate.

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Line of credit extended to joint venture.

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Line of credit extended to joint venture, amount outstanding.

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The number of sheet processing facilities operated by Steel Technologies.

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

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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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-Publisher AICPA
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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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For an unclassified balance sheet, amounts due from parties associated with the reporting entity as evidenced by a written promise to pay.

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The cash outflow associated with the investment in or advances to an entity in which the reporting entity shares control of the entity with another party or group.

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Equity Investments (Details) In Millions, unless otherwise specified			6 Months Ended				12 Months Ended			3 Months Ended		6 Months Ended					6 Months Ended
	Jul. 02, 2011 USD ($)	Dec. 31, 2010 USD ($)	Jul. 02, 2011 90 Basis Point [Member] Steel Technologies LLC [Member]	Jul. 02, 2011 250 Basis Point [Member] Steel Technologies LLC [Member]	Jul. 02, 2011 EURO [Member] Duferdofin Nucor S.r.l [Member] EUR (€)	Jul. 02, 2011 EURO [Member] Nucor [Member] EUR (€)	Dec. 31, 2010 NuMit [Member] USD ($)	Jul. 02, 2011 NuMit [Member] USD ($)	Apr. 30, 2010 NuMit [Member]	Jul. 02, 2011 Duferdofin Nucor S.r.l [Member] USD ($)	Jul. 03, 2010 Duferdofin Nucor S.r.l [Member] USD ($)	Jul. 02, 2011 Duferdofin Nucor S.r.l [Member] USD ($)	Jul. 03, 2010 Duferdofin Nucor S.r.l [Member] USD ($)	Dec. 31, 2010 Duferdofin Nucor S.r.l [Member] USD ($)	Sep. 30, 2010 Duferdofin Nucor S.r.l [Member]	Jul. 02, 2011 Nucor [Member] USD ($)	Jul. 02, 2011 Steel Technologies LLC [Member] USD ($)	Apr. 30, 2010 Steel Technologies LLC [Member]
Equity method investments	$ 841.4	$ 797.6					$ 229.1	$ 238.3		$ 566.8		$ 566.8		$ 531.9
Equity method investments, share of net assets										79.4		79.4
Difference between carrying amount and underlying equity										487.4		487.4
Step-up to fair value of equity method investment, portion related to identification of goodwill												349.9
Notes receivable, related parties																	40.0
Equity method investment, ownership percentage									50.00%	50.00%		50.00%						100.00%
Amortization expense and other purchase accounting adjustments associated with the fair value step-up										3.2	2.8	6.1	5.7
Interest rate per year in excess of Euribor as of date of the note												1.00%
Interest rate per year that was reset in excess of Euribor rate															1.00%
Investment in joint venture							221.3
Line of credit extended to joint venture																	97.5
Line of credit extended to joint venture, amount outstanding																	87.5
Interest rate on note to related party in excess of LIBOR																	0.90%
Interest rate on line of credit to related party in excess of LIBOR																	2.50%
Due from related parties, noncurrent					20.0					29.0		29.0
Total amount outstanding under equity method investment's applicable credit facilities					105.5
Equity method investment's credit facilities					112.5
Amount outstanding under equity method investment's credit facilities guaranteed by Nucor						€ 52.8										$ 76.4
Debt instrument - maturity date			October 21, 2014	April 1, 2012
Steel technologies sheet processing facilities	25