CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) shares in Millions, $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2021	Jun. 30, 2020	Jun. 30, 2021	Jun. 30, 2020
Income Statement [Abstract]
Revenue	$ 327.4	$ 322.7	$ 613.1	$ 657.1
Cost of goods sold excluding depreciation, depletion and amortization	259.4	250.1	492.5	524.0
Selling, general and administrative expenses	48.3	31.7	77.6	65.4
Depreciation, depletion and amortization	25.7	25.2	50.1	48.6
Change in value of contingent consideration	0.0	(5.8)	(0.1)	(5.5)
Gain on sale/disposal of assets and business, net	(0.1)	(0.1)	(1.6)	(0.1)
Operating income (loss)	(5.9)	21.6	(5.4)	24.7
Interest expense, net	10.3	11.4	20.7	22.8
Loss on extinguishment of debt	5.5	0.0	5.5	0.0
Other income, net	(0.5)	(0.6)	(0.9)	(1.2)
Income (loss) before income taxes	(21.2)	10.8	(30.7)	3.1
Income tax expense (benefit)	(0.7)	4.3	(5.4)	(0.6)
Net income (loss)	(20.5)	6.5	(25.3)	3.7
Amounts attributable to non-controlling interest	(0.2)	(0.1)	(0.2)	0.2
Net income (loss) attributable to U.S. Concrete	$ (20.3)	$ 6.6	$ (25.1)	$ 3.5
Earnings (loss) per share attributable to U.S. Concrete:
Basic earnings per share (in dollars per share)	$ (1.19)	$ 0.39	$ (1.49)	$ 0.21
Diluted earnings per share (in dollars per share)	$ (1.19)	$ 0.39	$ (1.49)	$ 0.21
Weighted average shares outstanding:
Basic (in shares)	17.0	16.6	16.9	16.6
Diluted (in shares)	17.0	16.6	16.9	16.6