Income Taxes - Schedule of Income Tax Provision Related to Continuing Operations (Details) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019
Income Tax Disclosure [Abstract]
Income tax benefit at federal statutory rate	$ (109,889)	$ (93,229)	$ (92,411)
Research credits	(4,727)	(3,081)	(10,511)
Change in valuation allowance	97,914	87,060	104,440
Non-cash interest expense on liability related to sales of future royalties	9,936	6,356	5,259
Non-cash royalty revenue related to sales of future royalties	(7,891)	(7,967)	(7,624)
Loss on revaluation of liability related to the sale of future royalties	4,940	0	0
Stock-based compensation	6,627	7,929	(672)
Other	3,647	3,425	2,132
Provision for income taxes	$ 557	$ 493	$ 613

Effective Income Tax Rate Reconciliation, Non-cash Royalty Revenue Related To Sales Of Future Royalties, Amount

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Amount 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 other nondeductible expenses.

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

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Amount of difference between reported income tax expense (benefit) and expected income tax expense (benefit) computed by applying domestic federal statutory income tax rates to pretax income (loss) from continuing operations, attributable to disposition of asset. Includes, but is not limited to, intra-entity transfer of asset other than inventory.

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The amount of income tax expense or benefit for the period computed by applying the domestic federal statutory tax rates to pretax income from continuing operations.

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