Stockholders' Equity - Schedule of Change in Stockholder's Equity (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jul. 01, 2017	Jul. 02, 2016	Jul. 01, 2017	Jul. 02, 2016
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			$ 8,254,708	$ 7,849,877
Total comprehensive income	$ 365,781	$ 286,156	744,280	463,850
Stock options			11,068	9,215
Issuance of stock under award plans, net of forfeitures			23,593	18,973
Amortization of unearned compensation			700	500
Treasury stock acquired				(5,173)
Dividends declared			(243,016)	(240,538)
Distributions to noncontrolling interests			(79,420)	(78,684)
Other				(2,378)
Stockholders' equity, end of period	8,711,913	8,015,642	8,711,913	8,015,642
Total Nucor Stockholders' Equity [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			7,879,865	7,477,816
Total comprehensive income			704,855	401,169
Stock options			11,068	9,215
Issuance of stock under award plans, net of forfeitures			23,593	18,973
Amortization of unearned compensation			700	500
Treasury stock acquired				(5,173)
Dividends declared			(243,016)	(240,538)
Other				(602)
Stockholders' equity, end of period	8,377,065	7,661,360	8,377,065	7,661,360
Noncontrolling Interests [Member]
Stockholders' Equity [Line Items]
Stockholders' equity, beginning of period			374,843	372,061
Total comprehensive income			39,425	62,681
Distributions to noncontrolling interests			(79,420)	(78,684)
Other				(1,776)
Stockholders' equity, end of period	$ 334,848	$ 354,282	$ 334,848	$ 354,282