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Income Taxes - Additional Information (Detail) $ in Millions	12 Months Ended
	Dec. 31, 2020 USD ($)
Income Taxes [Line Items]
Deferred tax assets increase in valuation allowance	$ 7.3
Federal net operating loss carryforwards	125.4
State NOLs	20.2
Federal
Income Taxes [Line Items]
Tax credits	$ 5.4
Operating loss carryforwards expiration beginning year	2035
Tax credit carryforwards expiration beginning year	2036
Net operating loss carryforwards, infinite life	$ 91.3
State
Income Taxes [Line Items]
Tax credits	$ 1.8
Tax credit carryforwards expiration beginning year	2036

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Income taxes line items.

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible domestic operating loss carryforwards. Excludes state and local operating loss carryforwards.

+ References

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Amount before allocation of valuation allowances of deferred tax asset attributable to deductible operating loss carryforwards that are not subject to expiration dates.

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