Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended				9 Months Ended
	Oct. 03, 2020		Sep. 28, 2019		Oct. 03, 2020		Sep. 28, 2019
Statement Of Comprehensive Income [Abstract]
Net earnings	$ 222,630		$ 293,587		$ 410,162		$ 1,236,657
Other comprehensive income:
Net unrealized income (loss) on hedging derivatives, net of income taxes of $2,000 and $(1,000) for the third quarter of 2020 and 2019, respectively, and $1,400 and $(2,500) for the first nine months of 2020 and 2019, respectively	6,387		(3,315)		4,888		(7,801)
Reclassification adjustment for settlement of hedging derivatives included in net income, net of income taxes of $700 and $500 for the third quarter of 2020 and 2019, respectively, and $2,300 and $500 for the first nine months of 2020 and 2019, respectively	2,113	[1]	1,615	[2]	6,712	[1]	1,501	[2]
Foreign currency translation gain (loss), net of income taxes of $0 for the third quarter and first nine months of 2020 and 2019	16,867		(14,306)		(24,103)		(5,219)
Net current-period other comprehensive income (loss)	25,367		(16,006)		(12,503)		(11,519)
Comprehensive income	247,997		277,581		397,659		1,225,138
Comprehensive income attributable to noncontrolling interests	(29,215)		(18,556)		(87,535)		(73,337)
Comprehensive income attributable to Nucor stockholders	$ 218,782		$ 259,025		$ 310,124		$ 1,151,801

[1] Includes $2,113 and $6,712 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2020, respectively. The tax impacts of those reclassifications were $700 and $2,300 in the third quarter and first nine months of 2020, respectively.

[2] Includes $1,615 and $1,501 of accumulated other comprehensive income (loss) reclassifications into cost of products sold for net losses on commodity contracts in the third quarter and first nine months of 2019, respectively. The tax impacts of those reclassifications were $500 in both the third quarter and first nine months of 2019.