Marketable Securities (Schedule Of Cost And Fair Value Of Cash, Cash Equivalents, And Marketable Securities) (Details) (USD $)	Mar. 31, 2015	Dec. 31, 2014
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	$ 18,654,745	$ 22,905,698
Gross Unrealized Gains	4,152	122
Gross Unrealized Losses	(3,076)	(33,769)
Fair value	18,655,821us-gaap_AvailableForSaleSecurities	22,872,051us-gaap_AvailableForSaleSecurities
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	999,084	1,998,001
Gross Unrealized Gains	196	62
Gross Unrealized Losses		(153)
Fair value	999,280	1,997,910
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	2,535,661	2,042,697
Gross Unrealized Losses	(1,561)	(6,827)
Fair value	2,534,100	2,035,870
Certificates of Deposit [Member]
Schedule of Available-for-sale Securities [Line Items]
Cost Basis	15,120,000	18,865,000
Gross Unrealized Gains	3,956	60
Gross Unrealized Losses	(1,515)	(26,789)
Fair value	$ 15,122,441	$ 18,838,271

Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale.

+ References

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This item represents the cost of debt and equity securities, which are categorized neither as held-to-maturity nor trading, net of adjustments including accretion, amortization, collection of cash, previous other-than-temporary impairments recognized in earnings (less any cumulative-effect adjustments recognized, as defined), and fair value hedge accounting adjustments, if any.

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