Long-Term Debt - Additional information (Detail) - USD ($)	3 Months Ended		6 Months Ended		12 Months Ended
	Jun. 30, 2016	Jun. 30, 2015	Jun. 30, 2016	Jun. 30, 2015	Dec. 31, 2014	Dec. 31, 2015
Debt Instrument [Line Items]
Maximum consolidated debt reduction for unrestricted cash and cash equivalents for debt covenant calculation			$ 200,000,000
Additional interest expense	$ 340,000	$ 317,000	672,000	$ 624,000
Maximum | Texas Industries Inc.
Debt Instrument [Line Items]
Acquisition integration expenses					$ 70,000,000
Minimum
Debt Instrument [Line Items]
Reduction of consolidated debt in the debt ratio calculation			$ 50,000,000
Including Acquisition Bridge Debt | Maximum
Debt Instrument [Line Items]
Debt covenant	3.50		3.50
Excluding Acquisition Bridge Debt | Maximum
Debt Instrument [Line Items]
Debt covenant	3.75		3.75
Revolving Facility
Debt Instrument [Line Items]
Credit facility commitment	$ 350,000,000		$ 350,000,000
Senior unsecured revolving facility, maturity period			5 years
Outstanding letters of credit	2,507,000	2,507,000	$ 2,507,000	2,507,000		$ 2,507,000
Trade Receivable Facility
Debt Instrument [Line Items]
Credit facility commitment	250,000,000		$ 250,000,000
Debt instrument maturity period			Sep. 30, 2016
Credit facility borrowing base	391,600,000	$ 450,791,000	$ 391,600,000	$ 450,791,000		$ 282,258,000
Trade Receivable Facility | London Interbank Offered Rate(LIBOR)
Debt Instrument [Line Items]
Basis spread on variable rate			0.70%
Term Loan Facility
Debt Instrument [Line Items]
Credit facility commitment	$ 250,000,000		$ 250,000,000
Floating Rate Notes, Due 2017
Debt Instrument [Line Items]
Maturity date			Jun. 30, 2017
Maturity year			2017
6.6% Senior Notes, Due 2018
Debt Instrument [Line Items]
Interest rate on notes	6.60%		6.60%
Maturity year			2018
Increase in annual interest expense due to ongoing amortization of the terminated value of the swap agreements			$ 1,400,000