ACQUISITIONS AND DIVESTITURES (Narrative) (Details)		3 Months Ended		12 Months Ended
	Aug. 26, 2021 USD ($)	Mar. 31, 2022 USD ($) item	Mar. 31, 2021 USD ($)	Dec. 31, 2021 USD ($)
Significant Acquisitions and Disposals [Line Items]
Cash		$ 148,200,000	$ 0.0
Goodwill		12,500,000
Gain on sale of property, plant & equipment and businesses		2,600,000	117,200,000
Amount of assets divested		0
Assets held for sale		0	0	$ 0
Acquisitions 2022 [Member]
Significant Acquisitions and Disposals [Line Items]
Total consideration		193,500,000
Cash		148,200,000
Amortizable intangible assets recognized		$ 9,000,000.0
Estimated weighted-average amortization period of intangible assets		7 years 1 month 6 days
Intangible assets amortization period, tax purposes		15 years
Goodwill		$ 0.0
Intangible assets, deductible for income tax purposes		9,000,000.0
Acquisitions 2021 [Member]
Significant Acquisitions and Disposals [Line Items]
Amortizable intangible assets recognized				685,500,000
Goodwill				537,100,000
Goodwill, deductible for income tax purposes				115,600,000
Immaterial Business Acquisitions [Member]
Significant Acquisitions and Disposals [Line Items]
Total consideration				$ 4,900,000
U.S. Concrete, Inc. [Member]
Significant Acquisitions and Disposals [Line Items]
Total consideration	$ 1,634,500,000	1,634,500,000
Cash	$ 1,268,500,000
Cash		1,634,500,000
Goodwill		537,100,000
Changes in carrying amount of goodwill		12,500,000
California [Member]
Significant Acquisitions and Disposals [Line Items]
Consideration transferred, net of assets divested			12,900,000
Gain on sale of property, plant & equipment and businesses			$ 114,700,000
Aggregates [Member]
Significant Acquisitions and Disposals [Line Items]
Goodwill
Aggregates [Member] | Texas [Member]
Significant Acquisitions and Disposals [Line Items]
Number of facilities acquired | item		5
Aggregates [Member] | Texas [Member] | Production Stage Properties [Member]
Significant Acquisitions and Disposals [Line Items]
Number of facilities acquired | item		3
Aggregates [Member] | Texas [Member] | Development Stage Property [Member]
Significant Acquisitions and Disposals [Line Items]
Number of facilities acquired | item		1
Aggregates [Member] | Texas [Member] | Aggregate Sales Yard [Member]
Significant Acquisitions and Disposals [Line Items]
Number of facilities acquired | item		1
Amortizable Intangible Asset Straight-Line Method [Member] | Acquisitions 2021 [Member]
Significant Acquisitions and Disposals [Line Items]
Estimated weighted-average amortization period of intangible assets		15 years