CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	12 Months Ended
	Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Total net sales	$ 18,795,316	$ 22,260,774	$ 18,408,850
Costs of goods sold	14,749,433	16,142,943	13,046,426
Gross profit	4,045,883	6,117,831	5,362,424
Selling, general and administrative expenses	588,621	545,621	643,976
Profit sharing	272,033	452,551	388,111
Amortization of intangible assets	34,048	27,837	29,232
Operating income	3,151,181	5,091,822	4,301,105
Interest expense, net of capitalized interest	76,484	91,538	57,209
Other (income) expense, net	(144,246)	(20,785)	34,826
Income before income taxes	3,218,943	5,021,069	4,209,070
Income tax expense	751,611	1,141,577	962,256
Net income	2,467,332	3,879,492	3,246,814
Net income attributable to noncontrolling interests	(16,450)	(16,818)	(32,748)
Net income attributable to Steel Dynamics, Inc.	$ 2,450,882	$ 3,862,674	$ 3,214,066
Basic earnings per share attributable to Steel Dynamics, Inc. stockholders (in dollars per share)	$ 14.72	$ 21.06	$ 15.67
Weighted average common shares outstanding (in shares)	166,552	183,393	205,115
Diluted earnings per share attributable to Steel Dynamics, Inc. stockholders, including the effect of assumed conversions when dilutive (in dollars per share)	$ 14.64	$ 20.92	$ 15.56
Weighted average common shares and share equivalents outstanding (in shares)	167,431	184,622	206,615
Dividends declared per share (in dollars per share)	$ 1.70	$ 1.36	$ 1.04
Unrelated parties
Total net sales	$ 18,115,312	$ 21,469,251	$ 18,376,743
Related Parties
Total net sales	$ 680,004	$ 791,523	$ 32,107