Employee Benefit Plan	3 Months Ended
Apr. 04, 2020
Compensation And Retirement Disclosure [Abstract]
Employee Benefit Plan	10. Employee Benefit Plan Nucor makes contributions to a Profit Sharing and Retirement Savings Plan for qualified employees based on the profitability of the Company. Nucor’s expense for these benefits totaled $11.6 million and $71.2 million in the first quarter of 2020 and 2019, respectively. The related liability for these benefits is included in salaries, wages and related accruals in the condensed consolidated balance sheets.

The entire disclosure for pension and other postretirement benefits.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-URI http://asc.fasb.org/topic&trid=2235017

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