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Income Taxes - Additional Information (Details) - USD ($) | 12 Months Ended
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Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
Income Tax Examination [Line Items] |  |  |
Provision for federal or state income taxes | $ 0 | $ 0 | $ 0
Remaining portion of net operating losses | 824,000,000 |  |
Gross unrecognized tax benefits | 7,200,000 | 6,100,000 |
Unrecognized interest or penalties | 0 | $ 0 | $ 0
U.S. Federal and State |  |  |
Income Tax Examination [Line Items] |  |  |
Net operating loss carryforwards | 837,000,000 |  |
U.S. Federal and State | Tax Year 2025 To 2037 |  |  |
Income Tax Examination [Line Items] |  |  |
Net operating loss carryforwards | 238,000,000 |  |
U.S. Federal and State | Indefinite |  |  |
Income Tax Examination [Line Items] |  |  |
Net operating loss carryforwards | 599,000,000 |  |
U.S. Federal Government |  |  |
Income Tax Examination [Line Items] |  |  |
US Federal tax credits carry forward | 81,000,000 |  |
Net operating loss for limited use | 13,500,000 |  |
U.S. Federal Government | Minimum |  |  |
Income Tax Examination [Line Items] |  |  |
Net operating losses limited for use utilized on an annual basis | 200,000 |  |
U.S. Federal Government | Maximum |  |  |
Income Tax Examination [Line Items] |  |  |
Net operating losses limited for use utilized on an annual basis | $ 1,400,000 |  |

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