SEGMENT REPORTING (Segment Financial Disclosure) (Details) - USD ($) $ in Thousands		3 Months Ended
		Mar. 31, 2020	Mar. 31, 2019	Dec. 31, 2019	Dec. 31, 2018
Segment Reporting Information [Line Items]
Total revenues	[1]	$ 1,049,242	$ 996,511
Gross profit		201,723	191,675
Depreciation, Depletion, Accretion and Amortization (DDA&A)		95,480	89,181
Cash and cash equivalents and restricted cash		120,273	31,108	$ 274,506	$ 44,404
Total assets		10,629,382	10,296,852	$ 10,648,793
Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	1,104,806	1,052,643
Total assets		10,362,404	10,132,398
Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	(55,564)	(56,132)
Aggregates [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	812,662	778,833
Aggregates [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	[1],[2]	868,226	834,965
Gross profit		194,131	185,716
Depreciation, Depletion, Accretion and Amortization (DDA&A)		77,136	72,521
Total assets	[3]	9,473,128	9,275,593
Aggregates [Member] | Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	(55,564)	(56,132)
Asphalt [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	139,789	132,090
Asphalt [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	[1],[4]	139,789	132,090
Gross profit		(2,435)	(3,272)
Depreciation, Depletion, Accretion and Amortization (DDA&A)		8,734	8,550
Total assets	[3]	563,630	564,103
Asphalt [Member] | Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	0	0
Concrete [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	94,765	83,637
Concrete [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	94,765	83,637
Gross profit		9,213	8,563
Depreciation, Depletion, Accretion and Amortization (DDA&A)		4,082	2,964
Total assets	[3]	322,044	288,797
Concrete [Member] | Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	0	0
Calcium [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	2,026	1,951
Calcium [Member] | Operating Segments [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	2,026	1,951
Gross profit		814	668
Depreciation, Depletion, Accretion and Amortization (DDA&A)		49	60
Total assets	[3]	3,602	3,905
Calcium [Member] | Intersegment Sales [Member]
Segment Reporting Information [Line Items]
Total revenues	[1]	0	0
Other Segments [Member]
Segment Reporting Information [Line Items]
Depreciation, Depletion, Accretion and Amortization (DDA&A)		5,479	5,086
Corporate [Member]
Segment Reporting Information [Line Items]
Total assets		$ 146,705	$ 133,346

[1] ¹ The geographic markets are defined by states/countries as follows: East market — Arkansas, Delaware, Illinois, Kentucky, Maryland, North Carolina, Pennsylvania, Tennessee, Virginia, and Washington D.C. Gulf Coast market — Alabama, Florida, Georgia, Louisiana, Mexico, Mississippi, Oklahoma, South Carolina and Texas West market — Arizona, California and New Mexico

[2] Includes product sales (crushed stone, sand and gravel, sand, and other aggregates), as well as freight & delivery costs that we pass along to our customers, and service revenues (see Note 4) related to aggregates.

[3] Certain temporarily idled assets are included within a segment's Identifiable Assets but the associated DDA&A is shown within Other in the DDA&A section above as the related DDA&A is excluded from segment gross profit.

[4] Includes product sales, as well as service revenues (see Note 4) from our asphalt construction paving business.