Description Of Business (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Description Of Business [Line Items]
Cumulative losses incurred from inception	(458,605,903)	$ (453,403,462)
Installed base	119
Scenario, Forecast [Member] | Minimum [Member]
Description Of Business [Line Items]
Annual plan to rebalance and reduce operating expenses, percentage	15.00%
Scenario, Forecast [Member] | Maximum [Member]
Description Of Business [Line Items]
Annual plan to rebalance and reduce operating expenses, percentage	20.00%