Segments (Tables)

12 Months Ended

Dec. 31, 2017

Segment Reporting [Abstract]

Segments

Nucor’s results by segment are as follows (in thousands):

	Year Ended December 31,
	2017			2016			2015
Net sales to external customers:
Steel mills	$	14,508,847		$	11,312,048		$	11,084,331
Steel products		4,000,606			3,687,448			3,966,895
Raw materials		1,742,940			1,208,626			1,388,050
	$	20,252,393		$	16,208,122		$	16,439,276
Intercompany sales:
Steel mills	$	2,925,321		$	2,070,077		$	2,152,157
Steel products		108,945			106,838			90,969
Raw materials		9,191,081			5,997,498			6,279,316
Corporate/eliminations		(12,225,347	)		(8,174,413	)		(8,522,442	)
	$	—		$	—		$	—
Depreciation expense:
Steel mills	$	414,670		$	377,627		$	381,352
Steel products		39,532			36,906			39,512
Raw materials		172,699			191,466			198,705
Corporate		8,932			7,193			6,188
	$	635,833		$	613,192		$	625,757
Amortization expense:
Steel mills	$	41,478		$	22,479		$	18,789
Steel products		20,825			21,998			23,932
Raw materials		28,925			29,385			31,539
	$	91,228		$	73,862		$	74,260
Earnings (loss) before income taxes and noncontrolling interests:
Steel mills	$	2,084,203		$	1,724,168		$	629,256
Steel products		206,805			249,970			276,048
Raw materials		129,296			(95,121	)		(283,938	)
Corporate/eliminations		(670,347	)		(580,358	)		(379,500	)
	$	1,749,957		$	1,298,659		$	241,866
Segment assets:
Steel mills	$	9,249,926		$	8,084,773		$	7,318,169
Steel products		2,737,486			2,544,344			2,485,122
Raw materials		3,396,110			3,235,237			3,123,190
Corporate/eliminations		457,736			1,359,164			1,400,488
	$	15,841,258		$	15,223,518		$	14,326,969
Capital expenditures:
Steel mills	$	359,215		$	375,996		$	248,532
Steel products		68,497			30,698			41,291
Raw materials		59,036			194,112			74,607
Corporate		20,326			16,871			338
	$	507,074		$	617,677		$	364,768

Schedule of Net Sale by Product to External Customers

Net sales by product were as follows (in thousands). Further product group breakdown is impracticable.

	Year Ended December 31,
	2017		2016		2015
Net sales to external customers:
Sheet	$	6,407,974	$	5,178,467	$	4,628,805
Bar		3,558,806		2,886,648		3,005,450
Structural		1,979,898		1,982,642		2,137,413
Plate		1,644,934		1,204,185		1,312,663
Tubular products		917,235		60,106		—
Steel products		4,000,606		3,687,448		3,966,895
Raw materials		1,742,940		1,208,626		1,388,050
	$	20,252,393	$	16,208,122	$	16,439,276