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- Definition

Estimate subsequent cost funding under plan.

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Number of performance obligations.

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Payment receivable for license agreement reimbursement of previously costs incurred.

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Revenue, Remaining Performance Obligation, Variable Consideration Amount

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Revenue, Remaining Performance Obligation, Variable Consideration Amount, Period

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- Definition

Upfront cash payment received.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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- Definition

Amount, after allowance for credit loss, of right to consideration in exchange for good or service transferred to customer when right is conditioned on something other than passage of time, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current.

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Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as noncurrent.

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Amount, excluding tax collected from customer, of revenue from satisfaction of performance obligation by transferring promised good or service to customer. Tax collected from customer is tax assessed by governmental authority that is both imposed on and concurrent with specific revenue-producing transaction, including, but not limited to, sales, use, value added and excise.

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License, Collaboration and Other Significant Agreements - International Collaboration and License Agreement with Otsuka Pharmaceutical Co. Ltd. (Details) $ in Thousands	3 Months Ended
	Mar. 31, 2022 USD ($) performance_obligation	Mar. 31, 2021 USD ($)	Mar. 31, 2017 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2020 USD ($)
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Recognized revenue	$ 61,699	$ 52,304
Deferred revenue	75,796
Short-term deferred revenue	10,440			$ 20,906
Deferred revenue, net of current portion	65,356			21,474
Accounts receivable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable	24,316	3,539		19,094	$ 3,045
Prepaid expenses and other current assets
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable	3,970	1,916		4,309	1,722
Accounts payable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue	319	0		3,171	$ 7,227
License, collaboration and other revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Recognized revenue	$ 20,251	21,896
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Number of performance obligations \| performance_obligation	3
Transaction price	$ 316,900
Reimbursement of costs			$ 200
Estimated current global development costs subsequent to March 31, 2017	243,700
Deferred revenue	10,221
Short-term deferred revenue	4,248
Deferred revenue, net of current portion	5,973
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Accounts receivable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable	11,300
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Prepaid expenses and other current assets
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Accounts receivable	1,200			1,300
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Accounts payable
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Deferred revenue				$ 900
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| License, collaboration and other revenue
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Recognized revenue	5,503	$ 6,972
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Licensed HIF Product
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible milestone payments (up to)	$ 17,000
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Licensed HIF Product \| Minimum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible milestone payments, period	12 months
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Licensed HIF Product \| Maximum
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible milestone payments, period	24 months
Otsuka Pharmaceutical Company. Ltd. \| Otsuka International Agreement \| Licensed Products
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Eligible milestone payments (up to)	$ 525,000
Otsuka Pharmaceutical Company. Ltd. \| Up Front Non Refundable And Non Creditable \| Otsuka International Agreement
Collaborative Arrangement and Arrangement Other than Collaborative [Line Items]
Upfront cash payment received	$ 73,000