Marketable Securities (Schedule Of Cost And Fair Value Of Marketable Securities) (Details) - USD ($) |
Dec. 31, 2017 |
Dec. 31, 2016 |
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Schedule of Available-for-sale Securities [Line Items] | ||
Cost Basis | $ 17,988,827 | $ 8,743,229 |
Gross Unrealized Gains | 197 | |
Gross Unrealized Losses | (56,886) | (6,319) |
Fair value | 17,931,941 | 8,737,107 |
Commercial Paper [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Cost Basis | 3,241,005 | 3,987,424 |
Gross Unrealized Losses | (2,505) | (1,684) |
Fair value | 3,238,500 | 3,985,740 |
Corporate Bonds [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Cost Basis | 14,747,822 | 4,035,805 |
Gross Unrealized Losses | (54,381) | (4,635) |
Fair value | $ 14,693,441 | 4,031,170 |
Certificates of Deposit [Member] | ||
Schedule of Available-for-sale Securities [Line Items] | ||
Cost Basis | 720,000 | |
Gross Unrealized Gains | 197 | |
Fair value | $ 720,197 |
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- Definition 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
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- Definition Amount before tax of unrealized gain in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Amount before tax of unrealized loss in accumulated other comprehensive income (AOCI) on investments in debt and equity securities classified as available-for-sale. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition 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. Reference 1: http://www.xbrl.org/2003/role/presentationRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
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