Cash Cash Equivalents And Marketable Securities [Line Items]

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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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.

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-Publisher FASB
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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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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- Definition

Amount of investment in debt and equity securities categorized neither as trading securities nor held-to-maturity securities and intended be sold or mature one year or operating cycle, if longer.

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- Definition

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- Definition

Amount of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Excludes cash and cash equivalents within disposal group and discontinued operation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
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-Section 45
-Paragraph 1
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- Definition

Fair value portion of currency on hand as well as demand deposits with banks or financial institutions. Includes other kinds of accounts that have the general characteristics of demand deposits. Also includes short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates.

+ References

No definition available.

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- Definition

Investment in short-term money-market instruments (such as commercial paper, banker's acceptances, repurchase agreements, government securities, certificates of deposit, and so forth) which are highly liquid (that is, readily convertible to known amounts of cash) and so near their maturity that they present an insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify as cash equivalents by definition. Original maturity means an original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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- Definition

The carrying value of securities purchased to be resold in reverse repurchase transactions as of the balance sheet date.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
-Paragraph 1
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- Definition

Debt (bills, notes or bonds) that are issued by the government of the United States which are short-term, highly liquid investments that are both readily convertible to known amounts of cash and so near their maturity that they present insignificant risk of changes in value because of changes in interest rates. Generally, only investments with original maturities of three months or less qualify under that definition. Original maturity means original maturity to the entity holding the investment. For example, both a three-month US Treasury bill and a three-year Treasury note purchased three months from maturity qualify as cash equivalents. However, a Treasury note purchased three-years ago does not become a cash equivalent when its remaining maturity is three months.

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Cash, Cash Equivalents and Marketable Securities - Schedule of Cash, Cash Equivalents and Marketable Securities (Detail) - USD ($)	Mar. 31, 2018	Dec. 31, 2017	Mar. 31, 2017	Jan. 01, 2017
Cash Cash Equivalents And Marketable Securities [Line Items]
Cash	$ 1,345,392
Money market funds	2,618,149
Reverse repurchase agreements	17,000,000
U.S. government agency securities	17,990,985
Available for Sale	34,990,985
Cash Equivalents	20,963,541	$ 20,023,337	$ 19,302,850	$ 12,015,061
Current Marketable Securities	17,974,600	$ 22,923,462
Available for Sale [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	183
Unrecognized Loss	(16,568)
Estimated Fair Value	34,974,600
Cash Equivalents	17,000,000
Current Marketable Securities	17,974,600
Cash [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	1,345,392
Cash Equivalents	1,345,392
Money Market Funds [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	2,618,149
Cash Equivalents	2,618,149
Reverse Repurchase Agreements [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Estimated Fair Value	17,000,000
Cash Equivalents	17,000,000
US Government Agencies Securities [Member]
Cash Cash Equivalents And Marketable Securities [Line Items]
Unrecognized Gain	183
Unrecognized Loss	(16,568)
Estimated Fair Value	17,974,600
Current Marketable Securities	$ 17,974,600