Fair Value Measurement - Schedule of Short Term Investments (Detail)	Sep. 30, 2019 USD ($)
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 28,207,073
Unrealized Gain	18,953
Market Value	28,226,026
United States Treasury Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	3,388,492
Unrealized Gain	2,872
Market Value	3,391,364
Financial and Corporate Debt Securities [Member]
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	24,818,581
Unrealized Gain	16,081
Market Value	$ 24,834,662

Amount, before tax, of unrealized gain in accumulated other comprehensive income (AOCI) on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amortized cost of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale).

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109979856&loc=d3e26610-111562

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-Name Accounting Standards Codification
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-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27161-111563

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