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Income Taxes - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Income Tax Contingency [Line Items]
Valuation allowance deferred tax asset change in amount	$ 58.2
Tax Credit Carryforward, Amount	2.0
California Tax Authority
Income Tax Contingency [Line Items]
Tax Credit Carryforward, Amount	3.8
Federal and State Tax Authorities
Income Tax Contingency [Line Items]
Operating loss carry forward, net	195.3
Federal Tax Authority
Income Tax Contingency [Line Items]
Operating loss carry forward, net	191.4
Tax Credit Carryforward, Amount	$ 14.4
Tax Credit Beginning Expiration Year	2036
Federal Tax Authority | Maximum
Income Tax Contingency [Line Items]
Operating loss carry forward, deductions	80.00%
State Tax Authority
Income Tax Contingency [Line Items]
Operating loss carry forward beginning expiration year	2030

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