Percentage of sharing in Phase 2 development costs.

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- Definition

Potential development and regulatory milestones.

+ References

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- Definition

Potential development milestones.

+ References

No definition available.

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- Definition

Sale of stock consideration received.

+ References

No definition available.

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- Definition

Sale of stock repurchased cash consideration.

+ References

No definition available.

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- Definition

Upfront and milestone payments received from license agreements.

+ References

No definition available.

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- Definition

Upfront and milestone payments received under license agreement.

+ References

No definition available.

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- Definition

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.

+ References

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- Definition

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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- Definition

Number of shares of stock issued as of the balance sheet date, including shares that had been issued and were previously outstanding but which are now held in the treasury.

+ References

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- Definition

Number of shares that have been repurchased during the period and have not been retired and are not held in treasury. Some state laws may govern the circumstances under which an entity may acquire its own stock and prescribe the accounting treatment therefore. This element is used when state law does not recognize treasury stock.

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License and Collaboration Agreements - Additional Information (Details) - USD ($)			1 Months Ended	3 Months Ended		6 Months Ended
	Feb. 12, 2024	Jul. 23, 2017	Apr. 30, 2018	Jun. 30, 2024	Jun. 30, 2023	Jun. 30, 2024	Jun. 30, 2023	Dec. 31, 2020
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue, excluding assessed tax				$ 23,489,000	$ 20,499,000	$ 45,128,000	$ 42,093,000
Non-cash royalty revenue related to the sales of future royalties
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Revenue, excluding assessed tax				16,790,000	$ 15,832,000	32,298,000	$ 32,693,000
Bristol Myers Squibb Company
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock shares repurchased	8,300,000
Sale of stock repurchased cash consideration	$ 3,000,000
Bristol Myers Squibb Company \| Purchase Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Shares issued (in shares)			8,284,600
Sale of stock consideration received			$ 850,000,000
Other Partner
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential future additional payments for development milestones				$ 40,000,000		$ 40,000,000
Nektar-358 \| Eli Lilly
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Percentage of sharing in Phase 2 development costs		75.00%
Nektar-358 \| Maximum \| Eli Lilly And Company
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential future additional development and regulatory milestones (up to)		$ 250,000,000
Bristol Myers Squibb Collaboration Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock shares repurchased	8,300,000
Sale of stock repurchased cash consideration	$ 3,000,000
Nektar's \| Nektar-358
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Received upfront and milestone payment		$ 150,000,000
Percentage of sharing in Phase 2 development costs		25.00%
Nektar's \| Bristol Myers Squibb Collaboration Agreement \| Nektar 214
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Upfront and milestone payments received from license agreements			$ 1,000,000,000
Nektar's \| Bristol Myers Squibb Collaboration Agreement \| Nektar 214 \| Milestone One
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential future additional payments for development milestones								$ 50,000,000