Net Sales and Gross Profit by Line of Business (Detail) - USD ($) $ in Thousands	3 Months Ended		6 Months Ended
	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016
Product Information [Line Items]
Net sales	$ 996,289	$ 915,436	$ 1,787,973	$ 1,649,396
Gross profit (loss)	274,094	247,431	421,160	392,681
Corporate
Product Information [Line Items]
Gross profit (loss)	314	(1,549)	(125)	(5,571)
Building Materials Business | Operating Segments
Product Information [Line Items]
Net sales	931,735	856,570	1,660,157	1,531,025
Gross profit (loss)	250,156	227,260	375,346	353,534
Building Materials Business | Operating Segments | Interproduct Sales
Product Information [Line Items]
Net sales	(99,538)	(81,191)	(165,162)	(135,145)
Magnesia Specialties | Operating Segments
Product Information [Line Items]
Net sales	64,554	58,866	127,816	118,371
Gross profit (loss)	23,624	21,720	45,939	44,718
Aggregates | Building Materials Business | Operating Segments | Reportable Subsegments
Product Information [Line Items]
Net sales	578,388	547,293	1,029,767	978,153
Gross profit (loss)	173,487	165,044	252,765	247,080
Ready Mixed Concrete | Building Materials Business | Operating Segments | Reportable Subsegments
Product Information [Line Items]
Net sales	241,894	214,947	464,275	401,799
Gross profit (loss)	26,863	25,301	46,655	43,200
Asphalt and Paving
Product Information [Line Items]
Net sales	111,975	88,081	138,577	101,918
Gross profit (loss)	20,358	12,867	15,568	6,591
Cement | Building Materials Business | Operating Segments | Reportable Subsegments
Product Information [Line Items]
Net sales	99,016	87,440	192,700	184,300
Gross profit (loss)	$ 29,448	$ 24,048	$ 60,358	$ 56,663