Stockholders' Equity (Schedule Of Changes In Stockholders' Equity) (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jul. 02, 2011	Jun. 30, 2012	Jul. 02, 2011
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			$ 7,706,580	$ 7,330,694
Total comprehensive income	94,687	337,681	320,741	590,903
Stock options			15,381	10,571
Issuance of stock under award plans, net of forfeitures			26,029	16,367
Amortization of unearned compensation			500	900
Dividends declared			(233,216)	(230,772)
Distributions to noncontrolling interests			(52,812)	(43,272)
Other			(644)
Stockholders' equity, end of period	7,782,559	7,675,391	7,782,559	7,675,391
Attributable To Nucor Corporation [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			7,474,885	7,120,070
Total comprehensive income			275,229	547,812
Stock options			15,381	10,571
Issuance of stock under award plans, net of forfeitures			26,029	16,367
Amortization of unearned compensation			500	900
Dividends declared			(233,216)	(230,772)
Other			(644)
Stockholders' equity, end of period	7,558,164	7,464,948	7,558,164	7,464,948
Attributable To Noncontrolling Interests [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			231,695	210,624
Total comprehensive income			45,512	43,091
Distributions to noncontrolling interests			(52,812)	(43,272)
Stockholders' equity, end of period	$ 224,395	$ 210,443	$ 224,395	$ 210,443