Income Taxes - Effective Income Tax Rate Reconciliation (Details)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
U.S. federal income tax at statutory rate	21.00%	21.00%	21.00%
State taxes (net of federal benefit)	3.26%	5.02%	9.31%
Stock-based compensation	(5.18%)	(3.24%)	17.70%
Permanent differences	(0.36%)	(0.18%)	(0.14%)
Federal research and development credit	0.58%	1.77%	6.43%
Change in valuation allowance	(11.62%)	(20.12%)	(44.33%)
Other	(0.82%)	0.26%	(1.99%)
Acquisition costs	0.00%	(0.02%)	(1.71%)
Expiration of tax attribute carryforwards	(7.63%)	(4.54%)	0.00%
Effective income tax rate	(0.77%)	(0.05%)	6.27%

Effective Income Tax Rate Reconciliation, Acquisition Costs, Percent

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Effective Income Tax Rate Reconciliation, Expiration of Tax Attribute Carryforwards, Percent

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Percentage of current income tax expense (benefit) and deferred income tax expense (benefit) pertaining to continuing operations.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 12
-Publisher FASB
-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

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Percentage of domestic federal statutory tax rate applicable to pretax income (loss).

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 235
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
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Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

Reference 3: http://www.xbrl.org/2003/role/disclosureRef
-Topic 740
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-Publisher FASB
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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations attributable to changes in the valuation allowance for deferred tax assets.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 740
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-Name Accounting Standards Codification
-Section 50
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-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

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Percentage of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rate to pretax income (loss) from continuing operation, attributable to expense for award under share-based payment arrangement. Excludes expense determined to be nondeductible upon grant or after for award under share-based payment arrangement.

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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-URI https://asc.fasb.org//1943274/2147482685/740-10-50-12

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Percentage of the difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying the domestic federal statutory income tax rates to pretax income (loss) from continuing operations applicable to state and local income tax expense (benefit), net of federal tax expense (benefit).

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