Income Taxes (Details) (USD $)	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Income Taxes [Abstract]
Income tax provision (benefit)	$ (989,000)	$ (362,000)	$ 0
Deferred tax assets and liabilities [Abstract]
Depreciation and amortization	5,770,000	6,165,000
R&E tax credit carry-forwards	5,270,000	5,025,000
NYS investment tax credit carry-forwards	1,090,000	1,095,000
AMT credit carry-forwards	211,000	211,000
Net operating loss carry-forwards	204,974,000	190,263,000
Capitalized research and development expenditures	20,280,000	25,231,000
Stock compensation	13,848,000	13,826,000
Other items	0	1,097,000
Total gross deferred tax assets	251,443,000	242,913,000
Less: Valuation allowance	(251,443,000)	(242,913,000)
Deferred tax assets:	0	0
Deferred tax liability - long term	(11,332,000)	(12,321,000)
Net deferred tax liability	(11,332,000)	(12,321,000)
Reconciliation of income taxes computed at the Federal statutory income tax rate to the actual effective income tax [Abstract]
U.S. Federal statutory rate	34.00%	(34.00%)	(35.00%)
State income taxes, net of Federal benefit	13.20%	(4.90%)	(5.40%)
Research and experimental tax credit	(15.80%)	(3.80%)	0.00%
Effect of federal and state tax rate changes	1.50%	8.70%	0.00%
Permanent differences	47.90%	3.20%	4.20%
Change in valuation allowance	(109.60%)	30.00%	36.20%
Income tax provision (benefit)	(28.80%)	(0.80%)	0.00%
Net operating loss carryforwards - federal	557,200,000
Net operating loss carryforwards - state	475,600,000
Net operating loss carry-forwards not reflected in deferred tax assets	18,200,000
Valuation allowance related to net operating loss carryforwards attributable to excess tax deductions for equity compensation	11,200,000
Unrecognized tax benefits	(989,000)	(362,000)	0
Deferred tax liability - long term	11,332,000	12,321,000
Tax Credit Carryforward, Amount	5,300,000
Income Taxes [Abstract]
Unrecognized tax benefits	2,661,000	2,661,000	2,661,000
Current year - increases	0	0
Current year - decreases	0	0
Settlements	0	0
Expired statuses	$ 0	$ 0