Marketable Securities (Details 2)	Dec. 31, 2017 USD ($)
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	$ 36,825,138
Unrealized Losses, Less than 12 Months	(194,303)
Fair Value, 12 Months or More	0
Unrealized Losses,12 Months or More	0
Fair Value, Total	36,825,138
Unrealized Losses, Total	(194,303)
Corporate Bond Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Fair Value, Less than 12 Months	36,825,138
Unrealized Losses, Less than 12 Months	(194,303)
Fair Value, 12 Months or More	0
Unrealized Losses,12 Months or More	0
Fair Value, Total	36,825,138
Unrealized Losses, Total	$ (194,303)

Amount of accumulated unrealized loss on investments in debt and equity securities classified as available-for-sale that have been in a continuous loss position for twelve months or longer.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section 50
-Paragraph 6
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