Revenue Recognition - Schedule of Company's Total Revenues by Category for each Reportable Segment (Detail) - USD ($) $ in Thousands	3 Months Ended
	Mar. 31, 2018	Mar. 31, 2017
Revenue Recognition [Line Items]
Products and Services	$ 753,305	$ 792,316
Freight	48,699	51,543
Total	802,004	843,859
Building Materials Business
Revenue Recognition [Line Items]
Products and Services	688,436	728,014
Freight	44,306	47,268
Total	732,742	775,282
Operating Segments | Mid-America Group | Building Materials Business
Revenue Recognition [Line Items]
Products and Services	167,890	177,407
Freight	10,891	11,612
Total	178,781	189,019
Operating Segments | Southeast Group | Building Materials Business
Revenue Recognition [Line Items]
Products and Services	77,563	86,726
Freight	2,676	3,556
Total	80,239	90,282
Operating Segments | West Group | Building Materials Business
Revenue Recognition [Line Items]
Products and Services	442,983	463,881
Freight	30,739	32,100
Total	473,722	495,981
Operating Segments | Magnesia Specialties
Revenue Recognition [Line Items]
Products and Services	64,869	64,302
Freight	4,393	4,275
Total	$ 69,262	$ 68,577