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Income Taxes - Additional Information (Detail) $ in Millions | 12 Months Ended
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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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- Definition 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 Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 8 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32632-109319 Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32621-109319 + Details
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