Stock-Based Compensation (Schedule Of Stock-Based Compensation Expense By Statement Of Operations) (Details) (USD $)	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Stock-based employee compensation expense	$ 463,000	$ 1,322,000	$ 841,000	$ 1,708,000
Cost of contract revenue
Stock-based employee compensation expense	4,000	30,000	10,000	40,000
Cost of product revenue
Stock-based employee compensation expense	0	31,000	20,000	40,000
Research and development expense
Stock-based employee compensation expense	87,000	564,000	224,000	739,000
Sales, marketing, general and administrative expense
Stock-based employee compensation expense	$ 372,000	$ 697,000	$ 587,000	$ 889,000