Disposal Group, Including Discontinued Operation, Contract With Customer Asset, Current.

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- Definition

Number Of Milestones

+ References

No definition available.

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- Definition

Payable for newdrug investigle milestone.

+ References

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- Definition

Payment for development milestones.

+ References

No definition available.

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- Definition

Percentage of sharing in Phase 2 development costs.

+ References

No definition available.

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- Definition

Potential development and regulatory milestones.

+ References

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- Definition

Potential development milestones.

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No definition available.

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- Definition

Sale of stock consideration received.

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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

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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.

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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)			1 Months Ended	12 Months Ended
	Feb. 12, 2024 USD ($) shares	Jul. 23, 2017 USD ($)	Apr. 30, 2018 USD ($) shares	Dec. 31, 2023 USD ($)	Dec. 31, 2024 USD ($) Milestones	Dec. 31, 2020 USD ($)
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Contract asset					$ 7,000,000
Bristol Myers Squibb Company
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock shares repurchased \| shares	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) \| 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
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
Nektar 0165 \| Biolojic Design Company [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Payable For Newdrug Investigle Milestone				$ 3,000,000
Number of Milestone \| Milestones					0
Nektar 0165 \| Maximum \| Biolojic Design Company [Member]
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Potential future additional payments for development milestones				35,000,000
Payment For Development Milestones				$ 18,000,000
Bristol Myers Squibb Collaboration Agreement
Collaborative Arrangements and Non-collaborative Arrangement Transactions [Line Items]
Sale of stock shares repurchased \| shares	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