SEGMENT INFORMATION - Schedule of Identifiable Property, Plant and Equipment Assets (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Segment Reporting Information [Line Items]
Total identifiable assets	$ 673.5
Total identifiable assets		$ 680.2	$ 636.3
Other products and corporate
Segment Reporting Information [Line Items]
Total identifiable assets	27.5
Total identifiable assets		29.7	27.6
Ready-mixed concrete | Operating Segments
Segment Reporting Information [Line Items]
Total identifiable assets	286.4
Total identifiable assets		295.5	266.6
Aggregate products | Operating Segments
Segment Reporting Information [Line Items]
Total identifiable assets	$ 359.6
Total identifiable assets		$ 355.0	$ 342.1