Basis of Interim Presentation (Policies)	9 Months Ended
Sep. 28, 2019
Organization Consolidation And Presentation Of Financial Statements [Abstract]
Recently Adopted Accounting Pronouncements	Recently Adopted Accounting Pronouncements – In the first quarter of 2019, Nucor adopted new guidance related to lease accounting using the modified retrospective approach, which permits companies to recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption without adjusting the comparative periods prior to adoption. The new lease guidance requires all lessees to recognize on the balance sheet right-of-use assets and lease liabilities for the rights and obligations created by lease arrangements with terms greater than 12 months, including operating leases. Expenses are recognized in the statement of earnings in a manner similar to previous accounting guidance. We elected the package of practical expedients permitted under the transition guidance within the new lease standard, which, among other things, allowed us to carry forward the historical lease classification. We also elected the practical expedient related to land easements, allowing us to carry forward our accounting treatment for land easements on existing agreements, and the short-term lease exemption policy such that the new lease guidance was applied to leases greater than one year in duration. The adoption of the new lease standard did not have a material impact on our consolidated financial statements as it resulted in an increase of 0.5% and 1.2% to our total assets and total liabilities, respectively, on our consolidated balance sheet at January 1, 2019. The new lease standard did not materially impact our consolidated net earnings and had no impact on our cash flows. Finance lease right-of-use assets and liabilities are presented separately from operating lease right-of-use assets and liabilities in the condensed consolidated balance sheet in accordance with the new lease standard. See Note 4 for further information. In the first quarter of 2019, we also adopted new accounting guidance related to tax effects of the Tax Cuts and Jobs Act of 2017. As a result of the adoption of the new guidance, we elected to reclassify stranded tax effects from accumulated other comprehensive income to retained earnings, effective January 1, 2019. The adoption of this new guidance did not have a material impact on the Company’s consolidated financial statements.

Basis of Interim Presentation (Policies)

9 Months Ended

Sep. 28, 2019

Organization Consolidation And Presentation Of Financial Statements [Abstract]

Recently Adopted Accounting Pronouncements

Recently Adopted Accounting Pronouncements – In the first quarter of 2019, Nucor adopted new guidance related to lease accounting using the modified retrospective approach, which permits companies to recognize a cumulative-effect adjustment to the opening balance of retained earnings in the period of adoption without adjusting the comparative periods prior to adoption. The new lease guidance requires all lessees to recognize on the balance sheet right-of-use assets and lease liabilities for the rights and obligations created by lease arrangements with terms greater than 12 months, including operating leases. Expenses are recognized in the statement of earnings in a manner similar to previous accounting guidance.

We elected the package of practical expedients permitted under the transition guidance within the new lease standard, which, among other things, allowed us to carry forward the historical lease classification. We also elected the practical expedient related to land easements, allowing us to carry forward our accounting treatment for land easements on existing agreements, and the short-term lease exemption policy such that the new lease guidance was applied to leases greater than one year in duration. The adoption of the new lease standard did not have a material impact on our consolidated financial statements as it resulted in an increase of 0.5% and 1.2% to our total assets and total liabilities, respectively, on our consolidated balance sheet at January 1, 2019. The new lease standard did not materially impact our consolidated net earnings and had no impact on our cash flows. Finance lease right-of-use assets and liabilities are presented separately from operating lease right-of-use assets and liabilities in the condensed consolidated balance sheet in accordance with the new lease standard. See Note 4 for further information.

In the first quarter of 2019, we also adopted new accounting guidance related to tax effects of the Tax Cuts and Jobs Act of 2017. As a result of the adoption of the new guidance, we elected to reclassify stranded tax effects from accumulated other comprehensive income to retained earnings, effective January 1, 2019. The adoption of this new guidance did not have a material impact on the Company’s consolidated financial statements.