Summary of Assets, Liabilities and Results of Operations for Significant Unconsolidated Joint Ventures (Detail) (Significant Unconsolidated Joint Ventures, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Significant Unconsolidated Joint Ventures
Schedule of Investments [Line Items]
Current assets	$ 343,129	$ 307,358
Noncurrent assets	212,587	174,431
Total assets	555,716	481,789
Current liabilities	129,105	112,589
Noncurrent liabilities	76,422	42,850
Total liabilities	205,527	155,439
Net sales	601,233	672,859	557,372
Gross profit	165,650	189,691	161,273
Income before income taxes	105,329	132,399	100,853
Net income	$ 71,561	$ 88,414	$ 69,974