CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME
Net income	$ 190,836	$ 204,827
Other comprehensive income (loss) - net unrealized gain (loss) on cash flow hedging derivatives, net of income tax	37	(171)
Comprehensive income	190,873	204,656
Comprehensive income attributable to noncontrolling interests	(3,496)	(499)
Comprehensive income attributable to Steel Dynamics, Inc.	$ 187,377	$ 204,157