Stockholders' Equity - Valuation Assumptions of Granted Stock Options (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Stockholders Equity [Line Items]
Weighted-average risk-free interest rate		1.21%
Dividend yield
Weighted-average expected volatility		48.59%
Total weighted-average expected forfeiture rate		2.97%
Weighted-average expected life (years)		5 years 10 months 24 days
Total weighted-average remaining vesting period in years	3 years 4 months 17 days	4 years 3 months 18 days	4 years 6 months 26 days
Total fair value of options granted		$ 4,064,000
Stock-based compensation expense-Cost of sales	278,000	60,000	42,000
Stock-based compensation expense-SG&A	1,374,000	1,039,000	963,000
Income tax benefit	$ (603,000)	$ (390,000)	$ (402,000)