Income Taxes (Schedule Of Effective Income Tax Rate) (Details)	12 Months Ended
	Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Income Taxes [Abstract]
Statutory federal income tax rate	(35.00%)	(35.00%)	(35.00%)
Tax credits	(3.00%)	(6.00%)	(14.00%)
State income taxes and other	(3.00%)	0.00%	(3.00%)
Valuation allowance	41.00%	41.00%	52.00%
Effective tax rate	0.00%	0.00%	0.00%