Property And Equipment (Schedule Of Property And Equipment) (Details) - USD ($)	Jun. 30, 2015	Dec. 31, 2014
Property, Plant and Equipment [Line Items]
Gross property and equipment	$ 10,995,226	$ 10,896,597
Less: Accumulated depreciation	(9,918,215)	(10,001,869)
Net property and equipment	1,077,011	894,728
Equipment [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	8,363,433	8,264,804
Equipment Held For Lease [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	303,412	303,412
Leasehold Improvements [Member]
Property, Plant and Equipment [Line Items]
Gross property and equipment	$ 2,328,381	$ 2,328,381