Stock Incentive Plans - Stock-Based Compensation Expense Related to Stock Options, RSUs and Restricted Stock (Detail) (USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 9,264	$ 9,169	$ 7,717
Tax benefit for expense associated with non-qualified options	(1,234)	(1,321)	(650)
Total stock-based compensation expense, net of tax	8,030	7,848	7,067
Cost of sales [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	422	412	317
Selling, general and administrative expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	4,351	4,316	3,575
Research and development expense [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	4,491	4,441	3,825
Operating expenses [Member]
Employee Service Share-based Compensation, Allocation of Recognized Period Costs [Line Items]
Total stock-based compensation expense	$ 8,842	$ 8,757	$ 7,400