Stockholders' Equity - Schedule of Changes in Stockholders' Equity (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 04, 2015	Jul. 05, 2014	Jul. 04, 2015	Jul. 05, 2014
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			$ 8,075,118	$ 7,910,278
Total comprehensive income	$ 187,139	$ 198,780	152,636	283,599
Stock options			7,557	7,617
Issuance of stock under award plans, net of forfeitures			18,384	19,556
Amortization of unearned compensation			500	400
Dividends declared			(239,763)	(237,560)
Distributions to noncontrolling interests			(39,347)	(37,877)
Stockholders' equity, end of period	7,975,085	7,946,013	7,975,085	7,946,013
Attributable to Nucor Corporation [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			7,772,470	7,645,769
Total comprehensive income			101,555	245,040
Stock options			7,557	7,617
Issuance of stock under award plans, net of forfeitures			18,384	19,556
Amortization of unearned compensation			500	400
Dividends declared			(239,763)	(237,560)
Stockholders' equity, end of period	7,660,703	7,680,822	7,660,703	7,680,822
Attributable to Noncontrolling Interests [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			302,648	264,509
Total comprehensive income			51,081	38,559
Distributions to noncontrolling interests			(39,347)	(37,877)
Stockholders' equity, end of period	$ 314,382	$ 265,191	$ 314,382	$ 265,191