Stockholders' Equity - Schedule of Change in Stockholder's Equity (Detail) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 30, 2019	Mar. 31, 2018
BALANCES, beginning of period	$ 10,201,968	$ 9,084,788
Net earnings	530,793	380,112
Other comprehensive income (loss)	(6,540)	5,315
Stock options exercised	$ 3,136	12,280
Stock options exercised (in shares)	(88)
Stock option expense	$ 312	350
Issuance of stock under award plans, net of forfeitures	18,715	15,241
Amortization of unearned compensation	600	700
Treasury stock value acquired	(72,830)	(29,193)
Cash dividends declared	(123,086)	(121,881)
Distributions to noncontrolling interests	(50,402)	(24,793)
BALANCES, end of period	10,502,666	9,322,919
Common Stock [Member]
BALANCES, beginning of period	$ 152,061	$ 151,960
BALANCES, shares at beginning of period	380,154	379,900
Stock options exercised		$ 84
Stock options exercised (in shares)		210
Issuance of stock under award plans, net of forfeitures		$ 17
Issuance of stock under award plans, net of forfeitures, shares		43
BALANCES, end of period	$ 152,061	$ 152,061
BALANCES, shares at end of period	380,154	380,153
Additional Paid-in Capital [Member]
BALANCES, beginning of period	$ 2,073,715	$ 2,021,339
Stock options exercised	233	10,103
Stock option expense	312	350
Issuance of stock under award plans, net of forfeitures	8,479	8,805
Amortization of unearned compensation	600	700
BALANCES, end of period	2,083,339	2,041,297
Retained Earnings [Member]
BALANCES, beginning of period	10,337,445	8,463,709
Net earnings	501,806	354,179
Cash dividends declared	(123,086)	(121,881)
Other	(1,886)
BALANCES, end of period	10,714,279	8,696,007
Accumulated Other Comprehensive Loss [Member]
BALANCES, beginning of period	(304,133)	(254,681)
Other comprehensive income (loss)	(6,540)	5,315
Other	1,886
BALANCES, end of period	(308,787)	(249,366)
Treasury Stock [Member]
BALANCES, beginning of period	$ (2,467,010)	$ (1,643,291)
BALANCES, shares at beginning of period	74,562	61,931
Stock options exercised	$ 2,903	$ 2,093
Stock options exercised (in shares)	(88)	(78)
Issuance of stock under award plans, net of forfeitures	$ 10,236	$ 6,419
Issuance of stock under award plans, net of forfeitures, shares	(306)	(240)
Treasury stock value acquired	$ (72,830)	$ (29,193)
Treasury stock acquired (in shares)	1,200	443
BALANCES, end of period	$ (2,526,701)	$ (1,663,972)
BALANCES, shares at end of period	75,368	62,056
Total Nucor Stockholders' Equity [Member]
BALANCES, beginning of period	$ 9,792,078	$ 8,739,036
Net earnings	501,806	354,179
Other comprehensive income (loss)	(6,540)	5,315
Stock options exercised	3,136	12,280
Stock option expense	312	350
Issuance of stock under award plans, net of forfeitures	18,715	15,241
Amortization of unearned compensation	600	700
Treasury stock value acquired	(72,830)	(29,193)
Cash dividends declared	(123,086)	(121,881)
BALANCES, end of period	10,114,191	8,976,027
Noncontrolling Interest [Member]
BALANCES, beginning of period	409,890	345,752
Net earnings	28,987	25,933
Distributions to noncontrolling interests	(50,402)	(24,793)
BALANCES, end of period	$ 388,475	$ 346,892