Marketable Securities - Schedule of Marketable Securities and Cash Equivalents (Details) $ in Thousands	Sep. 30, 2019 USD ($)
Cash And Cash Equivalents [Line Items]
Amortized Cost	$ 89,065
Unrealized Gains	1
Fair Value	89,066
Total Cash Equivalents [Member]
Cash And Cash Equivalents [Line Items]
Amortized Cost	78,977
Fair Value	78,977
Total marketable securities [Member]
Cash And Cash Equivalents [Line Items]
Amortized Cost	10,088
Unrealized Gains	1
Fair Value	10,089
Corporate Debt Securities [Member]
Cash And Cash Equivalents [Line Items]
Amortized Cost	1,997
Unrealized Gains	1
Fair Value	1,998
Commercial Paper [Member]
Cash And Cash Equivalents [Line Items]
Amortized Cost	8,091
Fair Value	8,091
Money Market Funds [Member]
Cash And Cash Equivalents [Line Items]
Amortized Cost	78,977
Fair Value	$ 78,977

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)
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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=118939692&loc=d3e27161-111563

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
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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), classified as current.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 326
-SubTopic 30
-Section 45
-Paragraph 1
-URI http://asc.fasb.org/extlink&oid=118942338&loc=SL82898722-210454

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