Segment Financial Disclosure (Detail) (USD $)	3 Months Ended
	Mar. 31, 2013		Mar. 31, 2012
Total Revenues
Net sales	$ 504,554,000		$ 499,851,000
Delivery revenues	33,608,000		36,031,000
Total revenues	538,162,000		535,882,000
Gross profit	17,655,000		21,958,000
Depreciation, depletion, accretion and amortization	75,597,000	[1]	85,167,000	[1]
Aggregates
Total Revenues
Net sales	359,000,000	[2]	355,600,000	[2]
Net sales	(33,600,000)	[2]	(31,100,000)	[2]
Net sales	325,400,000	[2]	324,500,000	[2]
Gross profit	24,800,000		34,000,000
Depreciation, depletion, accretion and amortization	55,900,000	[1]	62,400,000	[1]
Concrete
Total Revenues
Net sales	99,900,000	[3]	92,500,000	[3]
Net sales	0	[3]	(500,000)	[3]
Net sales	99,900,000	[3]	92,000,000	[3]
Gross profit	(10,000,000)		(12,300,000)
Depreciation, depletion, accretion and amortization	8,000,000	[1]	11,200,000	[1]
Asphalt Mix
Total Revenues
Net sales	67,300,000		71,400,000
Net sales	67,300,000		71,400,000
Gross profit	1,900,000		(600,000)
Depreciation, depletion, accretion and amortization	2,000,000	[1]	2,200,000	[1]
Cement
Total Revenues
Net sales	22,700,000	[4]	20,500,000	[4]
Net sales	(10,700,000)	[4]	(8,500,000)	[4]
Net sales	12,000,000	[4]	12,000,000	[4]
Gross profit	1,000,000		900,000
Depreciation, depletion, accretion and amortization	3,900,000	[1]	4,000,000	[1]
Other unallocated
Total Revenues
Depreciation, depletion, accretion and amortization	$ 5,800,000	[1]	$ 5,400,000	[1]

[1] The allocation of indirect depreciation to our operating segments was changed in the fourth quarter of 2012 to better align the presentation with how management views information internally. The 2012 DDA&A amounts presented above have been revised to conform to the 2013 presentation.

[2] Includes crushed stone, sand and gravel, sand, other aggregates, as well as transportation and service revenues associated with the aggregates business.

[3] Includes ready-mixed concrete, concrete block, precast concrete, as well as building materials purchased for resale.

[4] Includes cement and calcium products.