Investments - Debt Securities Available-For-Sale (Detail) $ in Thousands	Jun. 30, 2020 USD ($)
Fair Value, Less than 12 Months	$ 83,770
Unrealized Losses, Less than 12 Months	(43)
Fair Value	83,770
Unrealized Losses	(43)
Commercial Paper [Member]
Fair Value, Less than 12 Months	37,446
Unrealized Losses, Less than 12 Months	(17)
Fair Value	37,446
Unrealized Losses	(17)
Corporate Debt Securities [Member]
Fair Value, Less than 12 Months	46,324
Unrealized Losses, Less than 12 Months	(26)
Fair Value	46,324
Unrealized Losses	$ (26)

Amount of investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
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-SubTopic 10
-Section 50
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in continuous unrealized loss position for less than 12 months, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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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), in unrealized loss position without allowance for credit loss.

+ References

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Amount of accumulated unrealized loss on investment in debt security measured at fair value with change in fair value recognized in other comprehensive income (available-for-sale), in unrealized loss position, without allowance for credit loss. Includes beneficial interest in securitized financial asset.

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