Stock-Based Compensation - Summary of Nucor's RSU Activity (Detail) - Restricted Stock Units [Member] - $ / shares shares in Thousands	12 Months Ended
	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares	1,830	1,776	1,246
Granted, Shares	397	1,246	1,770
Vested, Shares	(997)	(1,166)	(1,207)
Canceled, Shares	(63)	(26)	(33)
Unvested at end of year, Shares	1,167	1,830	1,776
Unvested at beginning of year, Grant Date Fair Value	$ 47.33	$ 52.60	$ 59.09
Granted, Grant Date Fair Value	110.74	42.46	48.00
Vested, Grant Date Fair Value	57.09	50.10	52.43
Canceled, Grant Date Fair Value	49.54	49.75	57.09
Unvested at end of year, Grant Date Fair Value	$ 60.45	$ 47.33	$ 52.60