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Percentage of gross sale of common stock sold through sales agents commission rate.

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Percentage of ownership received in asset acquisition.

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Sale of equity aggregate maximum public offering amount.

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The cash outflow for cost incurred directly with the issuance of an equity security.

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The cash inflow from the additional capital contribution to the entity.

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The cash inflow from the sale of property, plant and equipment (capital expenditures), software, and other intangible assets.

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Amount of expense (reversal of expense) for expected credit loss on accounts receivable.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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Number of new stock issued during the period.

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Ratio applied to the conversion of stock split, for example but not limited to, one share converted to two or two shares converted to one.

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Description of the reverse stock split arrangement. Also provide the retroactive effect given by the reverse split that occurs after the balance sheet date but before the release of financial statements.

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Organization and Summary of Significant Accounting Policies - Additional Information (Detail) $ / shares in Units, $ in Thousands					3 Months Ended	6 Months Ended		12 Months Ended
	Jul. 02, 2025 USD ($) $ / shares shares	Jun. 08, 2025	Jun. 06, 2025	Dec. 02, 2024 USD ($)	Jun. 30, 2024	Jun. 30, 2025 USD ($)	Jun. 30, 2024 USD ($)	Dec. 31, 2024 USD ($)
Organization And Summary Of Significant Accounting Policies [Line Items]
Cash and investments in marketable securities						$ 175,903		$ 269,095
Aggregate maximum public offering amount						300,000
Accounts receivable, credit loss expense (reversal)						$ 0	$ 0
Reverse stock split, ratio					0.07		0.07	0.066667
Reverse stock split			Reverse Stock Split Amendment, to effect a reverse stock split of Nektar’s Common Stock at a ratio of one-for-fifteen, effective June 8, 2025.			one-for-fifteen reverse stock split		one-for-fifteen reverse stock split
Asset Purchase Agreement \| Asset Acquisition By Ampersand Capital Partners
Organization And Summary Of Significant Accounting Policies [Line Items]
Proceeds from sale of assets				$ 64,700
Ownership interest received				20.00%
Sales Agreement
Organization And Summary Of Significant Accounting Policies [Line Items]
Aggregate maximum public offering amount						$ 75,000
Percentage of gross sale of common stock sold through sales agents commission rate						3.00%
Common Stock
Organization And Summary Of Significant Accounting Policies [Line Items]
Reverse stock split, ratio		0.07
Common Stock \| 2025 Offering \| Subsequent Event
Organization And Summary Of Significant Accounting Policies [Line Items]
Sale and issuance of shares \| shares	4,893,618
Offering per share price \| $ / shares	$ 23.5
Net proceeds from issuance of common stock	$ 107,500
Underwriting discounts and commissions and offering costs	$ 7,500