Stock-Based Compensation (Tables)

12 Months Ended

Dec. 31, 2016

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Summary of Stock Option Plans Activity

A summary of activity under Nucor’s stock option plans is as follows (shares in thousands):

Year Ended December 31,	2016					2015					2014
	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		3,092		$	43.51		2,422		$	42.39		2,089		$	40.47
Granted		899		$	48.80		700		$	47.59		469		$	50.63
Exercised		(400	)	$	39.19		(10	)	$	42.34		(136	)	$	41.30
Canceled		—			—		(20	)	$	50.63		—			—
Outstanding at end of year		3,591		$	45.32		3,092		$	43.51		2,422		$	42.39
Options exercisable at end of year		1,557		$	40.80		1,531		$	39.35		1,263		$	40.40

Summary of Stock Options Outstanding

The following table summarizes information about stock options outstanding at December 31, 2016 (shares in thousands):

	Options Outstanding
Exercise Price	Options Outstanding		Options Exercisable		Weighted- Average Remaining Contractual Life
$35.76		531		531		5.4 years
$42.34		520		520		4.4 years
$44.51		506		506		6.4 years
$47.59		700		—		8.4 years
$48.80		899		—		9.4 years
$50.63		435		—		7.4 years
$35.76 - $50.63		3,591		1,557		7.2 years

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

The fair value was estimated using the Black-Scholes option-pricing model with the following assumptions:

	2016			2015			2014
Exercise price	$	48.80		$	47.59		$	50.63
Expected dividend yield		3.07	%		3.13	%		2.92	%
Expected stock price volatility		26.14	%		33.32	%		45.00	%
Risk-free interest rate		1.67	%		1.86	%		2.03	%
Expected life (in years)		6.5			6.5			6.5

Summary of Nucor's RSU Activity

A summary of Nucor’s RSU activity is as follows (shares in thousands):

Year Ended December 31,	2016					2015					2014
	Shares			Grant Date Fair Value		Shares			Grant Date Fair Value		Shares			Grant Date Fair Value
Restricted stock units:
Unvested at beginning of year		1,031		$	47.93		1,012		$	45.98		1,122		$	42.51
Granted		723		$	48.80		790		$	47.59		655		$	50.63
Vested		(681	)	$	48.09		(756	)	$	44.99		(752	)	$	44.90
Canceled		(33	)	$	46.44		(15	)	$	46.61		(13	)	$	42.66
Unvested at end of year		1,040		$	48.47		1,031		$	47.93		1,012		$	45.98
Shares reserved for future grants (stock options and RSUs)		8,706					10,349					11,851

Summary of Nucor's Restricted Stock Activity under AIP and LTIP

A summary of Nucor’s restricted stock activity under the AIP and the LTIP is as follows (shares in thousands):

Year Ended December 31,	2016					2015					2014
	Shares			Grant Date Fair Value		Shares			Grant Date Fair Value		Shares			Grant Date Fair Value
Restricted stock awards and units:
Unvested at beginning of year		63		$	48.07		65		$	48.20		73		$	45.49
Granted		123		$	44.03		136		$	47.07		127		$	50.35
Vested		(116	)	$	45.16		(138	)	$	47.15		(135	)	$	48.76
Canceled		(3	)	$	45.75		—			—		—			—
Unvested at end of year		67		$	45.77		63		$	48.07		65		$	48.20
Shares reserved for future grants		855					975					1,111