CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Net sales
Unrelated parties	$ 2,571,544	$ 2,814,486
Related parties	3,556	2,949
Total net sales	2,575,100	2,817,435
Costs of goods sold	2,159,871	2,383,865
Gross profit	415,229	433,570
Selling, general and administrative expenses	112,898	111,038
Profit sharing	21,454	23,677
Amortization of intangible assets	7,191	7,013
Operating income	273,686	291,842
Interest expense, net of capitalized interest	28,019	31,122
Other income, net	(2,589)	(6,343)
Income before income taxes	248,256	267,063
Income tax expense	57,420	62,236
Net income	190,836	204,827
Net income attributable to noncontrolling interests	(3,496)	(499)
Net income attributable to Steel Dynamics, Inc.	$ 187,340	$ 204,328
Basic earnings per share attributable to Steel Dynamics, Inc. stockholders	$ 0.88	$ 0.91
Weighted average common shares outstanding (in shares)	213,254	224,058
Diluted earnings per share attributable to Steel Dynamics, Inc. stockholders, including the effect of assumed conversions when dilutive (in dollars per share)	$ 0.88	$ 0.91
Weighted average common shares and share equivalents outstanding (in shares)	214,024	224,962
Dividends declared per share (in dollars per share)	$ 0.2500	$ 0.2400