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Income Taxes - Tax credit carryforward (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Operating Loss Carryforwards |
Operating loss carryforward offset (as a percent) | 80.00%
Federal Orphan Credit |
Operating Loss Carryforwards |
Tax credit carry forward amount | $ 1.2
California | Research and Development Credit |
Operating Loss Carryforwards |
Tax credit carry forward amount | $ 19.8

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- Definition The amount of the tax credit carryforward, before tax effects, available to reduce future taxable income under enacted tax laws. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 740 -SubTopic 10 -Section 50 -Paragraph 3 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=84230637&loc=d3e32559-109319 + Details
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