Net Sales By Product Line (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Business Combination, Separately Recognized Transactions
Net Sales	$ 491,220	$ 409,565	$ 841,757	$ 700,201
Aggregates
Business Combination, Separately Recognized Transactions
Net Sales	356,849	331,209	614,262	554,257
Asphalt
Business Combination, Separately Recognized Transactions
Net Sales	20,235	13,943	32,723	24,854
Ready Mixed Concrete
Business Combination, Separately Recognized Transactions
Net Sales	29,246	7,627	49,490	12,941
Road Paving
Business Combination, Separately Recognized Transactions
Net Sales	34,428	7,186	43,104	9,408
Total Aggregates Business
Business Combination, Separately Recognized Transactions
Net Sales	440,758	359,965	739,579	601,460
Magnesia Based Chemicals
Business Combination, Separately Recognized Transactions
Net Sales	35,524	34,145	71,923	69,305
Dolomitic Lime
Business Combination, Separately Recognized Transactions
Net Sales	14,443	15,103	29,415	28,882
Others
Business Combination, Separately Recognized Transactions
Net Sales	495	352	840	554
Specialty Products
Business Combination, Separately Recognized Transactions
Net Sales	$ 50,462	$ 49,600	$ 102,178	$ 98,741