Stock Based Compensation Expense Allocation (Details) (USD $)	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized	$ 8,900,000
Employee Service Share-based Compensation, Nonvested Awards, Total Compensation Cost Not yet Recognized, Period for Recognition	20 months
Allocated Share-based Compensation Expense, Net of Tax	6,976,000	9,649,000	12,328,000
Stock based compensation capitalized in Inventory	38,000	38,000
Stock Based Compensation capitalized in Deferred COGS	3,000	23,000
Cost of Product [Member]
Allocated Share-based Compensation Expense	567,000	864,000	1,172,000
Cost of Service [Member]
Allocated Share-based Compensation Expense	111,000	112,000	125,000
Cost of Revenues [Member]
Allocated Share-based Compensation Expense	678,000	976,000	1,297,000
Product Development [Member]
Allocated Share-based Compensation Expense	2,304,000	3,891,000	4,185,000
Selling and Marketing Expense [Member]
Allocated Share-based Compensation Expense	1,896,000	2,251,000	2,939,000
General and Administrative Expense [Member]
Allocated Share-based Compensation Expense	2,098,000	2,531,000	3,907,000
Operating Expense [Member]
Allocated Share-based Compensation Expense	6,298,000	8,673,000	11,031,000
Total Share based compensation costs prior to tax benefit [Member]
Allocated Share-based Compensation Expense	6,976,000	9,649,000	12,328,000
Tax benefit [Member]
Adjustments to Additional Paid in Capital, Income Tax Benefit from Share-based Compensation	$ 0	$ 0	$ 0