Outstanding Debt - Additional Information (Details) $ / shares in Units, shares in Thousands			3 Months Ended		12 Months Ended
	Mar. 07, 2025 USD ($)	Apr. 26, 2024 installment	Mar. 31, 2025 USD ($) $ / shares shares	Mar. 31, 2024 USD ($) shares	Dec. 31, 2024 USD ($) $ / shares
Outstanding Debt
Conversion of share settled debt into common stock			$ 866,000	$ 2,532,000
Extinguishment of debt upon conversion			100,000
Additional share liability recognized			600,000
Gain (loss) from debt extinguishment			(1,600,000)
Interest expense including amortization of debt discount			1,600,000	1,500,000
Amortization of debt discount			300,000	600,000
Principal amount			59,730,000		$ 60,030,000
Gain (Loss) from extinguishment of debt			$ (7,282,000)	$ (2,171,000)
Series C convertible preferred stock
Outstanding Debt
Number of shares issued to lenders in lieu of cash payments \| shares			(69)	(220)
Conversion of share settled debt into common stock			$ (866,000)	$ (2,532,000)
Short term convertible notes payable
Outstanding Debt
Principal amount			1,490,000		$ 1,895,000
Convertible notes payable
Outstanding Debt
Conversion price \| $ / shares					$ 0.5
Convertible notes payable \| Series C convertible preferred stock
Outstanding Debt
Period of which preferred stock can convert into common shares					30 days
8% unsecured \| Short term convertible notes payable
Outstanding Debt
Principal amount			$ 1,355,000		$ 1,760,000
Interest rate (in percent)			8.00%		8.00%
Conversion price \| $ / shares			$ 0.2		$ 0.5
Minimum \| Convertible notes payable \| Series C convertible preferred stock
Outstanding Debt
Conversion price \| $ / shares					$ 12.5
Notes
Outstanding Debt
Cash payments			$ 6,200,000
Number of shares issued to lenders in lieu of cash payments \| shares			27,900
Conversion of share settled debt into common stock			$ 7,300,000
Accrued interest expense on debt			1,100,000
Commercial Loan
Outstanding Debt
Term of debt instrument	22 months
Principal amount	$ 5,500,000
Interest rate (in percent)	8.00%
Number of installments for amortization \| installment		14
Original issue discount	$ 500,000
Debt Instrument, Term When Principal Payment Was Not Made	8 months
Modified convertible note
Outstanding Debt
Principal amount			$ 1,700,000
Long term convertible notes
Outstanding Debt
Term of debt instrument			2 years
Principal amount			$ 2,200,000
Interest rate (in percent)			11.00%
Long term convertible notes \| Minimum
Outstanding Debt
Conversion price \| $ / shares			$ 0.2
Long term convertible notes \| Maximum
Outstanding Debt
Conversion price \| $ / shares			$ 0.245
Convertible notes payable
Outstanding Debt
Det converted to common stock (in shares) \| shares			8,000
Conversion of shares			$ 1,900,000
Conversion price \| $ / shares			$ 0.24
Gain (Loss) from extinguishment of debt			$ (5,600,000)
Debt instrument, maximum extension period			24 months
Amended convertible note
Outstanding Debt
Det converted to common stock (in shares) \| shares			2,100
Conversion of shares			$ 400,000
Accrued interest expense			$ 31,000
Conversion price \| $ / shares			$ 0.2
Amended \| Modified convertible note
Outstanding Debt
Gain (Loss) from extinguishment of debt			$ 6,000

NORTHWEST BIOTHERAPEUTICS INC 10-Q