Condensed Consolidated Statements of Comprehensive Income (Loss) - USD ($) $ in Thousands		3 Months Ended
		Apr. 03, 2021	Apr. 04, 2020
Statement Of Comprehensive Income [Abstract]
Net earnings		$ 987,514	$ 54,379
Other comprehensive income (loss):
Net unrealized income (loss) on hedging derivatives, net of income taxes of $400 and $(800) for the first quarter of 2021 and 2020, respectively		999	(2,256)
Reclassification adjustment for settlement of hedging derivatives included in net income, net of income taxes of $100 and $700 for the first quarter of 2021 and 2020, respectively	[1]	501	2,056
Foreign currency translation gain (loss), net of income taxes of $0 for the first quarter of 2021 and 2020		13,801	(64,461)
Net current-period other comprehensive income (loss)		15,301	(64,661)
Comprehensive income (loss)		1,002,815	(10,282)
Comprehensive income attributable to noncontrolling interests		45,082	34,048
Comprehensive income (loss) attributable to Nucor stockholders		$ 957,733	$ (44,330)

[1] Includes $501 and $2,056 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the first quarter of 2021 and 2020, respectively. The tax impact of those reclassifications was $100 and $700 in the first quarter of 2021 and 2020, respectively.