Income Taxes (Schedule Of Deferred Income Tax Assets And Liabilities) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Current
Assets:
Accruals not currently deductible	$ 2,970,671	$ 3,721,183
Stock based compensation	13,290,429	12,044,953
Impairment loss on available-for-sale securities	0	0
Intangible Assets	0	0
Other	4,713,241	5,690,130
Total deferred income tax assets	20,974,341	21,456,266
Liabilities:
Excess tax over book depreciation	0	0
Patent costs	0	0
Unrealized gain on investments	0	0
Other	(558,249)	(527,417)
Net deferred income taxes	20,416,092	20,928,849
Non-Current
Assets:
Accruals not currently deductible	182,803	186,997
Stock based compensation	2,202,940	1,696,966
Impairment loss on available-for-sale securities	175,091	327,308
Intangible Assets	169,913	0
Other	40,203	3,609
Total deferred income tax assets	2,770,950	2,214,880
Liabilities:
Excess tax over book depreciation	(41,374,851)	(47,704,521)
Patent costs	(1,792,968)	(8,137,111)
Unrealized gain on investments	(10,482,468)	(3,146,585)
Other		0
Net deferred income taxes	$ (50,879,337)	$ (56,773,337)