Income Taxes - Reconciliation of Statutory Federal Income Tax Rate and the Effective Income Tax Rate (Detail)	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022	Dec. 31, 2021
Income Tax Disclosure [Abstract]
Income tax at statutory federal rate	21.00%	21.00%	21.00%
Executive and share-based compensation	(0.40%)	1.90%	0.60%
Subpart F Inclusion	0.00%	(3.40%)	0.00%
Foreign rate differential	0.00%	(2.70%)	(4.60%)
Change in effective state tax rates	(1.60%)	0.20%	(0.30%)
State income tax expense	4.80%	3.60%	2.00%
Research and development credits	14.10%		0.00%
Other permanent items	(1.50%)	0.00%	0.00%
Change in valuation allowance	(36.90%)	(20.60%)	(18.70%)
Provision for income taxes	(0.50%)	0.00%	0.00%

Effective income tax rate reconciliation subpart fInclusion.

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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
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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
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-Name Accounting Standards Codification
-Section S99
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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
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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 statutory income tax expense (benefit) outside of the country of domicile.

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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 nondeductible expense for share-based payment arrangement.

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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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