Joint Ventures - Summarized Information for Joint Ventures (Detail) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Schedule of Equity Method Investments [Line Items]
Net sales	$ 20,004	$ 18,083	$ 48,383	$ 52,745
Gross profit (loss)	4,437	3,364	9,051	10,644
Net income (loss)	$ 3,546	$ 2,580	$ 7,470	$ 8,082