BUSINESS COMBINATIONS - Schedule of Unaudited Pro Forma Information (Details) - USD ($) $ / shares in Units, $ in Millions	3 Months Ended	9 Months Ended
	Sep. 30, 2018	Sep. 30, 2018
Business Combinations [Abstract]
Revenue	$ 405.5	$ 1,153.1
Net income attributable to U.S. Concrete	$ 15.2	$ 27.4
Net income per share attributable to U.S. Concrete - basic (in dollars per share)	$ 0.92	$ 1.67
Net income per share attributable to U.S. Concrete - diluted (in dollars per share)	$ 0.92	$ 1.66