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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

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Commitments and Contingencies - Additional Information (Details) $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($) ft²	Dec. 31, 2020 USD ($)	Dec. 31, 2019 USD ($)
Operating Leased Assets [Line Items]
Weighted-average remaining lease term (in years)	4 years
Weighted-average discount rate (as a percent)	7.60%
Operating lease cost \| $	$ 2.8	$ 3.1	$ 2.9
Rent expense \| $			$ 1.4
Purchase commitments \| $	$ 6.4
Lease Agreement \| Oakwood Village, Ohio
Operating Leased Assets [Line Items]
Area of rentable space (in square feet)	19,800
Lease Agreement \| Mountain View, California
Operating Leased Assets [Line Items]
Area of rentable space (in square feet)	25,500
Lease Agreement \| Mountain View, California \| Maximum
Operating Leased Assets [Line Items]
Lease agreement, renewal term (in years)	5 years
Lease Agreement \| Mountain View, California
Operating Leased Assets [Line Items]
Area of rentable space (in square feet)	24,600
Sub-Lease Agreement \| Denver, Colorado
Operating Leased Assets [Line Items]
Area of rentable space (in square feet)	12,800