Outstanding Debt - Additional Information (Details) $ / shares in Units, shares in Thousands											1 Months Ended	12 Months Ended
	Nov. 14, 2025 USD ($) D $ / shares	Oct. 27, 2025 USD ($) installment	Jun. 30, 2025 USD ($) D $ / shares	Jun. 26, 2025 USD ($) installment	Mar. 07, 2025 USD ($) installment	Dec. 19, 2024 USD ($) D $ / shares	Oct. 18, 2024 USD ($) installment	Sep. 27, 2024 USD ($)	Apr. 26, 2024 USD ($) installment	Feb. 21, 2024 USD ($) item instrument tranche $ / shares	Nov. 30, 2025 USD ($) $ / shares	Dec. 31, 2025 USD ($) $ / shares shares	Dec. 31, 2024 USD ($) item $ / shares shares	Jun. 04, 2024 $ / shares
Outstanding Debt
Principal amount												$ 66,644,000	$ 60,030,000
Conversion of share settled debt into common stock												2,797,000	14,091,000
Extinguishment of debt upon conversion												1,500,000	1,000,000
Gain (loss) from debt extinguishment												(6,000,000)	4,300,000
Gain (Loss) from extinguishment of debt												$ (17,397,000)	(14,393,000)
Number of shares issued during the period													2,679,000
Accrued interest expense													200,000
Debt converted to common stock (in shares) \| shares												49,000
Amount of debt converted												$ 11,100,000
Loss from issuance of debt												(4,676,000)	(835,000)
Additional share liability recognized												$ 400,000	$ 700,000
Exercise price \| $ / shares														$ 0.4
Series C convertible preferred stock
Outstanding Debt
Issuance of Series C preferred stock for conversion of debt and accrued interest (in shares) \| shares													535
Common Stock
Outstanding Debt
Convertible notes shares of common stock \| shares												4,711	38,237
Conversion of share settled debt into common stock												$ 5,000	$ 38,000
Maximum
Outstanding Debt
Exercise price \| $ / shares													$ 0.24
March commercial loan
Outstanding Debt
Principal amount					$ 5,500,000
Interest rate (in percent)					8.00%
Term of debt instrument					22 months
Term when no principal repayments was made					8 months
Number of installments for amortization \| installment					14
Original issue discount					$ 500,000
June Commercial Loan
Outstanding Debt
Principal amount				$ 2,200,000
Interest rate (in percent)				8.00%
Term when no principal repayments was made				8 months
Number of installments for amortization \| installment				14
Debt instrument, written notice period for redemption				22 months
Notes
Outstanding Debt
Convertible notes shares of common stock \| shares												96,700	53,000
Conversion of share settled debt into common stock												$ 25,900,000	$ 19,400,000
Cash payments												19,700,000	14,800,000
Accrued interest expense on debt												$ 1,800,000	$ 1,700,000
Notes \| Common Stock
Outstanding Debt
Convertible notes shares of common stock \| shares												96,700	53,000
Conversion of share settled debt into common stock													$ 19,400,000
Cash payments												$ 19,700,000	14,800,000
Accrued interest expense on debt													1,700,000
Extinguishment of debt upon conversion													1,000,000
Commercial Loan
Outstanding Debt
Principal amount									$ 11,000,000
Interest rate (in percent)									8.00%
Term of debt instrument									22 months
Term when no principal repayments was made									8 months
Number of installments for amortization \| installment									14
Original issue discount									$ 1,000,000
Promissory note
Outstanding Debt
Principal amount								$ 2,000,000
Amortization of debt discount								140,000
Additional debt discount								$ 140,000
Amortization of debt discount period								5 days
Debt instrument, written notice period for redemption								5 days
October commercial loan
Outstanding Debt
Principal amount		$ 5,500,000					$ 2,200,000
Interest rate (in percent)		8.00%					8.00%
Term of debt instrument		22 months					22 months
Term when no principal repayments was made		8 months					8 months
Number of installments for amortization \| installment		14					14
Original issue discount		$ 500,000					$ 200,000
February Convertible Notes
Outstanding Debt
Principal amount										$ 1,800,000
Interest rate (in percent)										8.00%
Term of debt instrument										1 year
Purchase price										$ 1,600,000
February Convertible Notes \| Series C convertible preferred stock
Outstanding Debt
Conversion price \| $ / shares										$ 12.5
Number of common stock shares issued upon conversion \| item										25
Modified convertible note
Outstanding Debt
Principal amount													1,500,000
Long term convertible notes
Outstanding Debt
Principal amount												$ 15,100,000	$ 8,600,000
Interest rate (in percent)													11.00%
Term of debt instrument												24 months	2 years
Gain (Loss) from extinguishment of debt												$ (11,400,000)
Number of shares issued during the period												2,000,000
Accrued interest expense												$ 200,000
Debt converted to common stock (in shares) \| shares												7,800
Debt instrument, exchanged from previously executed non dilutive financial instrument												$ 3,000,000	$ 300,000
Financial instrument exchanged from outstanding interest												700,000
Proceeds from issuance of debt													8,300,000
Convertible notes at fair value												17,600,000
Loss from issuance of debt												$ 2,600,000
Interest Expense, Debt													$ 300,000
Long term convertible notes \| Minimum
Outstanding Debt
Interest rate (in percent)												11.00%
Conversion price \| $ / shares												$ 0.19	$ 0.285
Long term convertible notes \| Maximum
Outstanding Debt
Interest rate (in percent)												12.00%
Conversion price \| $ / shares												$ 0.245	$ 0.38
Long term convertible notes \| Senior convertible notes
Outstanding Debt
Principal amount												$ 15,100,000
Two-year convertible notes
Outstanding Debt
Term of debt instrument												2 years
One-year convertible notes
Outstanding Debt
Principal amount													$ 5,500,000
Term of debt instrument												1 year	1 year
Period of which preferred stock can convert into common shares													30 days
Number of common stock shares issued upon conversion \| item													25
One-year convertible notes \| Minimum \| Series C convertible preferred stock
Outstanding Debt
Conversion price \| $ / shares													$ 10
One-year convertible notes \| Maximum \| Series C convertible preferred stock
Outstanding Debt
Conversion price \| $ / shares													$ 11.5
One-year convertible notes \| Senior convertible notes
Outstanding Debt
Interest rate (in percent)													11.00%
Convertible notes payable
Outstanding Debt
Gain (Loss) from extinguishment of debt													$ 8,700,000
Number of shares issued during the period												$ 1,400,000
Accrued interest expense												$ 200,000
Debt converted to common stock (in shares) \| shares												7,100
Conversion price \| $ / shares													$ 0.5
Debt instrument, maximum extension period													24 months
Convertible notes payable \| Series C convertible preferred stock
Outstanding Debt
Conversion price \| $ / shares													$ 12.5
Period of which preferred stock can convert into common shares													30 days
Convertible notes payable \| Maximum
Outstanding Debt
Conversion price \| $ / shares											$ 0.22
Convertible notes payable \| 11% unsecured
Outstanding Debt
Principal amount											$ 300,000
Interest rate (in percent)											11.00%
Term of debt instrument											2 years
Convertible notes payable \| 11% unsecured \| Minimum
Outstanding Debt
Conversion price \| $ / shares											$ 0.21
Yorkville Note
Outstanding Debt
Principal amount						$ 5,000,000
Convertible notes shares of common stock \| shares												12,500
Conversion price \| $ / shares						$ 0.315
Amount of debt converted												$ 2,800,000
Threshold percentage of stock price trigger						95.00%
Threshold consecutive trading days \| D						5
Convertible notes at fair value	$ 10,100,000					$ 5,800,000						$ 6,400,000	$ 5,900,000
Loss from issuance of debt	(2,100,000)					800,000
December Yorkville Note
Outstanding Debt
Principal amount						5,000,000
Convertible notes shares of common stock \| shares												21,500
Proceeds from issuance of debt						$ 4,700,000
Percentage of original issue discount						7.00%
Amount of debt converted												$ 5,000,000
June Yorkville Note
Outstanding Debt
Principal amount			$ 3,000,000
Conversion price \| $ / shares			$ 0.2932
Proceeds from issuance of debt			$ 2,900,000
Percentage of original issue discount			5.00%
Threshold percentage of stock price trigger			95.00%
Threshold consecutive trading days \| D			5
November yorkville Note
Outstanding Debt
Principal amount	$ 5,000,000
Conversion price \| $ / shares	$ 0.29
Proceeds from issuance of debt	$ 4,800,000
Percentage of original issue discount	5.00%
Threshold percentage of stock price trigger	95.00%
Threshold consecutive trading days \| D	5
Amended \| February Convertible Notes
Outstanding Debt
Gain (Loss) from extinguishment of debt										$ (1,300,000)
Number of tranches warrants \| tranche										16
Number of debt instruments \| instrument										10
Amended \| Modified convertible note
Outstanding Debt
Gain (Loss) from extinguishment of debt												$ 47,000	$ (100,000)
Conversion price $0.2932 per share \| June Yorkville Note
Outstanding Debt
Maximum debt that can be converted in a month			$ (800,000)
Conversion price $0.29 per share \| November yorkville Note
Outstanding Debt
Maximum debt that can be converted in a month	$ 1,000,000

NORTHWEST BIOTHERAPEUTICS INC 10-K