Quarterly Financial Data (Detail) (USD $) In Thousands, except Per Share data, unless otherwise specified	3 Months Ended																12 Months Ended
	Dec. 31, 2013		Sep. 30, 2013		Jun. 30, 2013		Mar. 31, 2013		Dec. 31, 2012		Sep. 30, 2012		Jun. 30, 2012		Mar. 31, 2012		Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Quarterly Financial Data [Line Items]
Revenues	$ 1,219,872	[1]	$ 1,300,978		$ 1,288,464		$ 1,146,763		$ 1,276,823		$ 1,208,402		$ 1,089,833		$ 966,763		$ 4,956,077	$ 4,541,821	$ 3,820,574
Income before income taxes	84,847	[1]	107,045		59,224		59,592		147,684		155,882		112,290		51,550		310,708	467,406	130,293
Net income	51,789	[1]	64,095		34,948		36,232		93,202		103,900		73,517		31,109		187,064	301,728	78,579
Net income attributable to noncontrolling interests	162	[1]	205		276		54		(75)		430		516		(184)		697	687	303
Net income attributable to the Company	$ 51,627	[1]	$ 63,890		$ 34,672		$ 36,178		$ 93,277		$ 103,470		$ 73,001		$ 31,293		$ 186,367	$ 301,041	$ 78,276
Basic	$ 0.49	[1],[2]	$ 0.60	[2]	$ 0.32	[2]	$ 0.34	[2]	$ 0.87	[2]	$ 0.97	[2]	$ 0.69	[2]	$ 0.30	[2]	$ 1.74	$ 2.83	$ 0.74
Diluted	$ 0.48	[1],[2]	$ 0.59	[2]	$ 0.31	[2]	$ 0.33	[2]	$ 0.85	[2]	$ 0.95	[2]	$ 0.68	[2]	$ 0.29	[2]	$ 1.71	$ 2.77	$ 0.73

[1] Net income for the quarter ended December 31, 2013 includes a net reduction of $4.4 million related to certain items that should have been recorded in a prior period. These items decreased diluted net income per share attributable to the Company’s stockholders by $0.04 for the quarter.

[2] Net income per share attributable to the Company’s stockholders for the four quarters of each fiscal year may not sum to the total for the fiscal year because of the different number of shares outstanding during each period.