CONSOLIDATED STATEMENTS OF INCOME - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Sep. 30, 2022	Sep. 30, 2021	Sep. 30, 2022	Sep. 30, 2021
Net sales
Unrelated parties	$ 5,438,747	$ 5,081,476	$ 16,814,051	$ 13,072,657
Related parties	212,960	6,812	620,436	25,536
Total net sales	5,651,707	5,088,288	17,434,487	13,098,193
Costs of goods sold	4,187,278	3,487,659	12,304,203	9,497,606
Gross profit	1,464,429	1,600,629	5,130,284	3,600,587
Selling, general and administrative expenses	132,627	157,526	403,019	461,686
Profit sharing	105,122	113,880	373,333	244,868
Amortization of intangible assets	6,836	7,178	21,158	22,054
Operating income	1,219,844	1,322,045	4,332,774	2,871,979
Interest expense, net of capitalized interest	25,347	12,704	67,683	44,871
Other (income) expense, net	(13,975)	6,776	2,472	26,886
Income before income taxes	1,208,472	1,302,565	4,262,619	2,800,222
Income tax expense	289,997	302,406	1,022,138	649,105
Net income	918,475	1,000,159	3,240,481	2,151,117
Net income attributable to noncontrolling interests	(4,150)	(9,396)	(12,671)	(27,556)
Net income attributable to Steel Dynamics, Inc.	$ 914,325	$ 990,763	$ 3,227,810	$ 2,123,561
Basic earnings per share attributable to Steel Dynamics, Inc. stockholders (in dollars per share)	$ 5.07	$ 4.89	$ 17.33	$ 10.22
Weighted average common shares outstanding (in shares)	180,264	202,450	186,288	207,704
Diluted earnings per share attributable to Steel Dynamics, Inc. stockholders, including the effect of assumed conversions when dilutive (in dollars per share)	$ 5.03	$ 4.85	$ 17.21	$ 10.15
Weighted average common shares and share equivalents outstanding (in shares)	181,613	204,167	187,531	209,222
Dividends declared per share (in dollars per share)	$ 0.34	$ 0.26	$ 1.02	$ 0.78