Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2011

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary Of Stock Option Plans Activity

	2011					2010					2009
	Shares			Weighted - Average Exercise Price		Shares			Weighted - Average Exercise Price		Shares			Weighted - Average Exercise Price
Number of shares under option:
Outstanding at beginning of year		983		$	29.14		1,060		$	21.95		1,299		$	20.80
Granted		560		$	42.34		242		$	41.43		—			—
Exercised		(387	)	$	20.96		(319	)	$	14.60		(239	)	$	15.69
Canceled		—			—		—			—		—			—
Outstanding at end of year		1,156		$	38.26		983		$	29.14		1,060		$	21.95
Options exercisable at end of year		354		$	29.67		741		$	25.12		1,060		$	21.95

Summary Of Stock Options Outstanding

	Options Outstanding						Options Exercisable
Range of Exercise Prices	Number Outstanding		Weighted- Average Remaining Contractual Life		Weighted- Average Exercise Price		Number Exercisable		Weighted- Average Exercise Price
$25.00 - $30.00		201		0.7 years	$	28.86		201	$	28.86
30.01 -   35.00		153		0.2 years	$	30.73		153	$	30.73
35.01 -   40.00		—		—		—		—		—
40.01 -   42.34		802		9.1 years	$	42.07		—		—
$25.00 - $42.34		1,156		6.5 years	$	38.26		354	$	29.67

Schedule Of Grant Date Fair Value Black-Scholes Option-Pricing Model Assumptions

	2011			2010
Exercise price	$	42.34		$	41.43
Expected dividend yield		3.42	%		3.48	%
Expected stock price volatility		49.40	%		50.58	%
Risk-free interest rate		2.39	%		2.75	%
Expected life (in years)		6.5			6.5

RSU [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary Of Nucor's Restricted Stock Unit Activity

	2011					2010					2009
				Grant Date					Grant Date					Grant Date
	Shares			Fair Value		Shares			Fair Value		Shares			Fair Value
Restricted stock units:
Unvested at beginning of year		1,203		$	49.96		1,464		$	54.69		1,139		$	67.67
Granted		490		$	42.34		462		$	43.05		1,147		$	43.91
Vested		(713	)	$	50.04		(709	)	$	55.24		(805	)	$	57.58
Canceled		(18	)	$	46.06		(14	)	$	49.52		(17	)	$	60.44
Unvested at end of year		962		$	46.09		1,203		$	49.96		1,464		$	54.69
Shares reserved for future grants (stock options and RSUs)		13,695					14,777					15,878

AIP And LTIP [Member]

Share-based Compensation Arrangement by Share-based Payment Award [Line Items]

Summary Of Nucor's Restricted Stock Unit Activity

	2011					2010					2009
				Grant Date					Grant Date					Grant Date
	Shares			Fair Value		Shares			Fair Value		Shares			Fair Value
Restricted stock awards and units:
Unvested at beginning of year		141		$	44.62		240		$	50.75		375		$	61.57
Granted		118		$	46.41		131		$	44.82		256		$	32.16
Vested		(165	)	$	47.13		(230	)	$	51.13		(391	)	$	48.96
Canceled		—			—		—			—		—			—
Unvested at end of year		94		$	42.46		141		$	44.62		240		$	50.75
Shares reserved for future grants		1,482					1,600					1,731