Short-Term Investments - Summary of Short-term Investments (Details) - USD ($) $ in Thousands	Jun. 30, 2019	Dec. 31, 2018
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	$ 10,983	$ 42,163
Gross Unrealized Gains	4
Gross Unrealized Loss		(17)
Fair Value	10,987	42,146
Corporate Bonds and Commercial Paper
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	5,989	37,168
Gross Unrealized Gains	3
Gross Unrealized Loss		(17)
Fair Value	5,992	37,151
U.S. Government Securities
Schedule Of Available For Sale Securities [Line Items]
Amortized Cost	4,994	4,995
Gross Unrealized Gains	1
Fair Value	$ 4,995	$ 4,995

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).

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Amount, before tax, of unrealized loss 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).

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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

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-Publisher FASB
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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).

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
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