Balance Sheet Components - Available-for-Sale Investments in Unrealized Loss Position (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 months	$ 29,195
Unrealized Loss, Less than 12 months	(7)
Corporate bonds/notes
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 months	10,128
Unrealized Loss, Less than 12 months	(4)
U.S. government securities
Debt Securities, Available-for-sale [Line Items]
Fair Value, Less than 12 months	19,067
Unrealized Loss, Less than 12 months	$ (3)

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.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 320
-SubTopic 10
-Section 50
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=82897076&loc=d3e27337-111563

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- Definition

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.

+ References

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- Definition

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+ References

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