Quarterly Information - Schedule of Quarterly Information (Unaudited) (Parenthetical) (Detail) - USD ($) $ in Thousands	3 Months Ended				12 Months Ended
	Jul. 03, 2021	Dec. 31, 2020	Oct. 03, 2020	Apr. 04, 2020	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Quarterly Financial Information [Line Items]
Losses and impairments of assets					$ 62,161	$ 613,640	$ 66,916
Net benefit related to state tax credits		$ 39,700
Net benefit related to CARES Act carryback provision		48,200
Duferdofin Nucor S.r.l. [Member]
Quarterly Financial Information [Line Items]
Losses and impairments of assets		184,000		$ 287,800		483,500
Tax benefit related to investment		201,900
Aggregate Assets Impaired [Member]
Quarterly Financial Information [Line Items]
Impairment of assets		130,200
Raw Materials [Member] | Unproved Natural Gas Well Assets [Member]
Quarterly Financial Information [Line Items]
Losses and impairments of assets	$ 42,000
Impairment of assets		27,000
Steel Products [Member]
Quarterly Financial Information [Line Items]
Restructuring charge			$ 16,400
Steel Mills [Member]
Quarterly Financial Information [Line Items]
Losses and impairments of assets						$ 103,200	$ 20,000
Steel Mills [Member] | Inventory and Long-lived Assets [Member]
Quarterly Financial Information [Line Items]
Impairment of assets		$ 103,200