UNAUDITED SUPPLEMENTARY DATA (Details) - USD ($)	3 Months Ended															12 Months Ended
	Dec. 31, 2015	Sep. 30, 2015	Jun. 30, 2015	Mar. 31, 2015	Dec. 31, 2014		Sep. 30, 2014		Jun. 30, 2014		Mar. 31, 2014		Sep. 30, 2013	Jun. 30, 2013	Mar. 31, 2013	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Total revenues	$ 857,285,000	$ 1,038,460,000	$ 895,143,000	$ 631,293,000	$ 755,027,000		$ 873,579,000		$ 791,143,000		$ 574,420,000					$ 3,422,181,000	$ 2,994,169,000	$ 2,770,709,000
Gross profit	253,929,000	291,290,000	234,449,000	77,865,000	169,660,000		209,042,000		174,788,000		34,092,000					857,533,000	587,582,000	426,880,000
Operating earnings	173,037,000	212,206,000	153,776,000	10,759,000	99,892,000	[1]	140,331,000	[1]	103,246,000	[1]	194,669,000	[1]				549,778,000	538,138,000	190,404,000
Earnings (loss) from continuing operations	93,560,000	126,202,000	49,819,000	(36,667,000)	38,349,000	[1]	67,781,000	[1]	46,511,000	[1]	54,505,000	[1]				232,914,000	207,146,000	20,756,000
Net earnings (loss)	$ 88,888,000	$ 123,805,000	$ 48,162,000	$ (39,678,000)	$ 38,022,000	[1]	$ 66,939,000	[1]	$ 45,967,000	[1]	$ 53,995,000	[1]				$ 221,177,000	$ 204,923,000	$ 24,382,000
Basic earnings (loss) per share from continuing operations	$ 0.70	$ 0.95	$ 0.37	$ (0.28)	$ 0.29		$ 0.51		$ 0.35		$ 0.42					$ 1.75	$ 1.58	$ 0.16
Diluted earnings (loss) per share from continuing operations	0.69	0.93	0.37	(0.28)	0.29		0.51		0.35		0.41					1.72	1.56	0.16
Basic net earnings (loss) per share	0.67	0.93	0.36	(0.30)	0.29		0.51		0.35		0.41					1.66	1.56	0.19
Diluted net earnings (loss) per share	$ 0.65	$ 0.91	$ 0.36	$ (0.30)	$ 0.28		$ 0.50		$ 0.35		$ 0.41					$ 1.64	$ 1.54	$ 0.19
Gain on sale of properties and businesses													$ 9,027,000	$ 21,183,000	$ 2,802,000	$ 9,927,000	$ 244,222,000	$ 39,250,000
Cement And Concrete [Member]
Gain on sale of properties and businesses											$ 227,910,000						$ 227,910,000

[1] Includes a $227,910 thousand pretax gain on the sale of our cement and concrete businesses in the Florida area as described in Note 19, primarily recorded in the first quarter.