Investments - Schedule of Investments by Security Type (Detail) - USD ($) $ in Thousands	Mar. 31, 2020	Dec. 31, 2019
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	$ 20,247	$ 29,689
Gross Unrealized Gain		3
Gross Unrealized Loss	(10)	(2)
Fair Value	20,237	29,690
Commercial Paper [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	11,466	11,957
Fair Value	11,466	11,957
Corporate Bonds [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	8,781	17,732
Gross Unrealized Gain		3
Gross Unrealized Loss	(10)	(2)
Fair Value	$ 8,771	$ 17,733

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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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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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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