Commitments and Contingencies - Additional Information (Details) $ in Millions	Sep. 30, 2019 USD ($)
San Mateo Facility
Other Commitments [Line Items]
Standby letter of credit issued	$ 5.0

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

No definition available.

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