Stock-Based Compensation - Summary of Nucor's Restricted Stock Unit ("RSU") Activity (Detail) - Restricted Stock Units [Member] shares in Thousands	9 Months Ended
	Sep. 30, 2023 $ / shares shares
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Unvested at beginning of year, Shares | shares	1,003
Granted, Shares | shares	831
Vested, Shares | shares	(870)
Canceled, Shares | shares	(12)
Unvested at September 30, 2023, Shares | shares	952
Unvested at beginning of year, Grant Date Fair Value Per Share | $ / shares	$ 98.66
Granted, Grant Date Fair Value Per Share | $ / shares	133.03
Vested, Grant Date Fair Value Per Share | $ / shares	102.72
Canceled, Grant Date Fair Value Per Share | $ / shares	103.58
Unvested at September 30, 2023, Grant Date Fair Value Per Share | $ / shares	$ 124.91