Debt	6 Months Ended
Jul. 04, 2020
Debt Disclosure [Abstract]
Debt	18. Debt In May 2020, Nucor issued $500.0 million of 2.000% Notes due 2025 and $500.0 million of 2.700% Notes due 2030. Net proceeds of the issuances were $989.4 million. Costs of $8.4 million associated with the issuances have been capitalized and will be amortized over the life of the notes.

The entire disclosure for information about short-term and long-term debt arrangements, which includes amounts of borrowings under each line of credit, note payable, commercial paper issue, bonds indenture, debenture issue, own-share lending arrangements and any other contractual agreement to repay funds, and about the underlying arrangements, rationale for a classification as long-term, including repayment terms, interest rates, collateral provided, restrictions on use of assets and activities, whether or not in compliance with debt covenants, and other matters important to users of the financial statements, such as the effects of refinancing and noncompliance with debt covenants.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-URI http://asc.fasb.org/topic&trid=2208564

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