CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) shares in Thousands, $ in Thousands		3 Months Ended
		Mar. 31, 2019	Mar. 31, 2018
CONDENSED CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME [Abstract]
Total revenues	[1]	$ 996,511	$ 854,474
Cost of revenues		804,836	695,140
Gross profit		191,675	159,334
Selling, administrative and general expenses		90,268	78,340
Gain on sale of property, plant & equipment and businesses		7,297	4,164
Other operating expense, net		(4,271)	(3,963)
Operating earnings		104,433	81,195
Other nonoperating income, net		3,129	5,071
Interest expense, net		32,934	37,774
Earnings from continuing operations before income taxes		74,628	48,492
Income tax expense (benefit)		10,693	(4,903)
Earnings from continuing operations		63,935	53,395
Loss on discontinued operations, net of tax		(636)	(416)
Net earnings		63,299	52,979
Other comprehensive income, net of tax
Deferred gain on interest rate derivative		0	2,496
Amortization of prior interest rate derivative loss		55	66
Amortization of actuarial loss and prior service cost for benefit plans		235	1,091
Other comprehensive income		290	3,653
Comprehensive income		$ 63,589	$ 56,632
Basic earnings (loss) per share
Continuing operations		$ 0.48	$ 0.40
Discontinued operations		0.00	0.00
Net earnings		0.48	0.40
Diluted earnings (loss) per share
Continuing operations		0.48	0.40
Discontinued operations		0.00	(0.01)
Net earnings		$ 0.48	$ 0.39
Weighted-average common shares outstanding
Basic		132,043	132,690
Assuming dilution		133,054	134,359
Depreciation, depletion, accretion and amortization		$ 89,181	$ 81,439
Effective tax rate from continuing operations		14.30%	(10.10%)

[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, Texas and the BahamasWest market - Arizona, California and New Mexico