Income Taxes (Schedule Of Components Of Deferred Tax Asset) (Details) - USD ($)	Dec. 31, 2016	Dec. 31, 2015
Income Taxes [Abstract]
Current accruals	$ 1,638,298	$ 1,687,951
Deferred revenue	126,631	269,797
Depreciation and amortization	2,131,933	2,269,341
Deferred compensation	1,464,533	1,389,832
Net operating loss carryovers	33,943,745	32,744,557
Deferred tax assets	39,305,140	38,361,478
Valuation allowance	(39,000,095)	(37,912,693)
Net deferred tax assets before deferred tax liabilities	305,045	448,785
Accounting method changes	(305,045)	(448,785)
Net deferred tax assets