Income Taxes - Additional Information (Detail) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Unrecognized tax benefits	$ 65.1	$ 75.6	$ 31.7
California Franchise Tax Board [Member]
Deferred tax assets, tax credit carryforwards, research	68.7	66.0
Domestic Tax Authority [Member]
Operating loss carryforwards, not subject to expiration	4,300.0
Deferred tax assets, tax credit carryforwards, research	184.1	85.1
Domestic Tax Authority [Member] \| California Franchise Tax Board [Member]
Net operating loss carryforwards	2,900.0	1,500.0
State and Local Jurisdiction [Member]
Net operating loss carryforwards	5,900.0	$ 3,600.0
United Kingdom [Member]
Net operating loss carryforwards	$ 333.0

Operating loss carryforwards, not subject to expiration.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible research tax credit carryforwards.

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Amount of operating loss carryforward, before tax effects, available to reduce future taxable income under enacted tax laws.

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The total amount of unrecognized tax benefits that, if recognized, would affect the effective tax rate.

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