Joint Ventures - Summarized Information for Joint Ventures (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended
	Mar. 31, 2013	Mar. 31, 2012
Schedule of Equity Method Investments [Line Items]
Net sales	$ 10,664	$ 12,805
Gross profit (loss)	1,104	1,825
Net income (loss)	$ 1,058	$ 1,314