Stock-Based Compensation Expense from Stock Options (Detail) (Stock Options, USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	$ 172	$ 74	$ 288	$ 148
Income tax benefit
Stock-based compensation expense after income taxes	172	74	288	148
Cost of revenue
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	2	5	5	8
Research and development
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	12	(5)	20	65
Selling and marketing
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	72	81	132	117
General and administrative
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Stock-Based Compensation Expense	$ 86	$ (7)	$ 131	$ (42)