Summarized Information for Joint Ventures (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
Schedule of Equity Method Investments [Line Items]
Net sales	$ 15,880	$ 16,783	$ 28,685	$ 34,863
Gross profit (loss)	2,608	3,211	4,433	7,535
Net income (loss)	$ 2,610	$ 2,646	$ 3,924	$ 5,502