Leases - Additional Information (Details) $ in Thousands	1 Months Ended		12 Months Ended
	Dec. 31, 2020 USD ($) ft²	Jun. 30, 2020 USD ($) ft²	Dec. 31, 2020 USD ($) ft²	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)
Lessee Lease Description [Line Items]
Operating lease, term of contract	10 years	8 years	10 years
Operating leases, minimum lease payments	$ 90,300	$ 10,100	$ 90,300	$ 13,391
Operating lease, option to extend	The lease is subject to two options to extend the lease term for a period of eight years each.	eight years
Operating lease, existence of option to extend	true	true
Operating lease, allowance for tenant improvements	$ 12,600	$ 1,000	$ 12,600
Operating lease, space delivered month and year			2020-08
Operating lease, option to extend lease term	8 years
Operating lease, option to increase allowance for tenant improvements	$ 5,500		$ 5,500
Weighted average remaining term	6 years 2 months 12 days		6 years 2 months 12 days
Operating lease, incremental borrowing rate				10.00%
Weighted average discount rate	7.30%		7.30%
Lease cost			$ 2,700
Short-term lease costs			200
Right-of-use assets	$ 12,781		12,781
Operating lease, liabilities	18,110		18,110
Short-term portion of operating lease liability	$ 2,867		$ 2,867
Operating lease, liability, current, statement of financial position [extensible list]	us-gaap:OtherCurrentLiabilitiesMember		us-gaap:OtherCurrentLiabilitiesMember
Operating lease liabilities, noncurrent	$ 15,243		$ 15,243
Rent expense				$ 1,600	$ 1,600
Operating lease Undiscounted amount	4,153		$ 4,153
Operating lease, lease not yet commenced, description			Total undiscounted future minimum lease payments do not include approximately $90.3 million related to the Company’s Brisbane lease that has not yet commenced.
Operating lease, leases commence year			2021
Minimum sublease rent income			$ 100
Operating lease, lease not yet commenced, existence of option to terminate			false
Deposits for letters of credit	$ 200		$ 200
Hayward, California
Lessee Lease Description [Line Items]
Square feet of space leased | ft²		36,303
Hayward, California | Executive Offices Research and Development and Business Operations
Lessee Lease Description [Line Items]
Square feet of space leased | ft²	136,293		136,293
Brisbane, California
Lessee Lease Description [Line Items]
Square feet of space leased | ft²	109,237		109,237
Operating lease expiration year			2031
Operating lease commencement year			2021
Operating lease Undiscounted amount	$ 90,300		$ 90,300
Minimum
Lessee Lease Description [Line Items]
Operating lease expiration year			2025
Minimum | Hayward, California | Executive Offices Research and Development and Business Operations
Lessee Lease Description [Line Items]
Operating lease expiration year			2025
Maximum
Lessee Lease Description [Line Items]
Operating lease expiration year			2029
Operating lease, lease not yet commenced, term of contract	10 years		10 years
Maximum | Hayward, California | Executive Offices Research and Development and Business Operations
Lessee Lease Description [Line Items]
Operating lease expiration year			2029