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Stockholders' Equity - Common stock (Details)															3 Months Ended			9 Months Ended		12 Months Ended
	Aug. 14, 2025 shares	Jul. 11, 2025 USD ($)	Jul. 10, 2025	Jun. 23, 2025 USD ($) BusinessDay $ / shares shares	Jun. 18, 2025 shares	Jun. 17, 2025 USD ($) $ / shares shares	May 02, 2025 USD ($) shares	Mar. 07, 2025 USD ($)	Mar. 04, 2025 USD ($) $ / shares shares	Feb. 13, 2025 USD ($) $ / shares shares	Aug. 09, 2024 USD ($)	May 09, 2024 USD ($) shares	May 08, 2024 shares	May 05, 2024 USD ($) $ / shares shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($)	Jun. 30, 2024 USD ($) shares	Sep. 30, 2025 USD ($) $ / shares shares	Sep. 30, 2024 USD ($)	Dec. 31, 2024 USD ($) $ / shares	Jun. 30, 2025 USD ($)	Jun. 16, 2025	May 19, 2025 $ / shares	Mar. 31, 2025 USD ($)	Mar. 31, 2024 USD ($)	Dec. 31, 2023 USD ($)
Class of Stock [Line Items]
Common stock, par value (in dollars per share) | $ / shares															$ 0.001			$ 0.001		$ 0.001
Class of warrant outstanding | shares															5,753,802			5,753,802
Fair value															$ 0			$ 0		$ 0
Excess of fair value of instruments issued over cash received																		1,389,000
Change in fair value of warrants																		800,000
Change in fair value of derivative instruments																$ (960,000)		2,631,000	$ (5,654,000)
Stockholders' deficit															$ 5,054,000	(5,174,000)	$ (7,625,000)	$ 5,054,000	(5,174,000)	(8,949,000)	$ 3,034,000			$ (23,641,000)	$ (4,837,000)	$ (1,348,000)
Number of shares issuable upon exercise | shares															1			1
Letter Agreement [Member] | Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Potential cash payment		$ 500,000													$ 2,300,000			$ 2,300,000
Modification period		30 days
Potential financing percentage		50.00%	90.00%
Support letter participation rights period		12 months
Financing percentage after modification period		90.00%
Series A Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares																							$ 0.4373
Series B Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares																							$ 0.4373
Series A Warrant and Series B Warrant [Member] | Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Fair value of warrant liability reclassified to equity											$ 5,200,000
Minimum [Member] | Letter Agreement [Member] | Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Stockholders' deficit		$ 3,000,000
Common Stock [Member]
Class of Stock [Line Items]
Stockholders' deficit															$ 132,000	$ 6,000	$ 6,000	132,000	$ 6,000	6,000	$ 92,000			17,000	$ 5,000	$ 5,000
Issue and sale of share | shares															34,388,496		1,439,988
Common Stock [Member] | Series A Warrant [Member] | Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Restricted beneficial ownership level result of exercise of warrant to receive pre-funded warrant														4.99%
Common Stock [Member] | Series B Warrant [Member]
Class of Stock [Line Items]
Number of shares issued | shares							21,482,492
Common Stock [Member] | Series B Warrant [Member] | Amendment and Restatements May 2024 Private Placement [Member]
Class of Stock [Line Items]
Restricted beneficial ownership level result of exercise of warrant to receive pre-funded warrant														9.99%
February 2025 SPEA Agreements
Class of Stock [Line Items]
Common stock, par value (in dollars per share) | $ / shares										$ 0.001
Warrant exercise price (in dollars per share) | $ / shares										$ 1.12
Aggregate purchase price										$ 3,700,000
Purchase price of share | $ / shares										$ 0.125
Maturity date										Feb. 13, 2026
Interest rate										10.00%
Proceeds from private placement										$ 4,200,000
February 2025 SPEA Agreements | SPEA Warrants [Member]
Class of Stock [Line Items]
Aggregate purchase price										4,200,000
February 2025 SPEA Agreements | February 2025 Warrants [Member]
Class of Stock [Line Items]
Fair value										500,000
Change in fair value of derivative instruments																		2,200,000
February 2025 SPEA Agreements | Common Stock [Member]
Class of Stock [Line Items]
Aggregate principal amount										$ 3,300,000
Number of securities called by warrant or right | shares										3,002,009
May 2024 Purchase Agreement
Class of Stock [Line Items]
Aggregate principal amount										$ 3,200,000
Financing expense																		3,100,000
May 2024 Purchase Agreement | Series A Warrant [Member]
Class of Stock [Line Items]
Fair value										2,700,000
Excess of fair value of instruments issued over cash received																		3,700,000
Carrying value of warrants exchanged															$ 3,700,000			3,700,000
May 2024 Purchase Agreement | Common Stock [Member] | Series A Warrant [Member]
Class of Stock [Line Items]
Number of shares issued | shares													3,591,532
May 2024 Purchase Agreement | Exchange Notes
Class of Stock [Line Items]
Fair value										3,800,000
Change in fair value of derivative instruments																		300,000
May 2024 Purchase Agreement | Funding Notes
Class of Stock [Line Items]
Fair value										4,000,000
Change in fair value of derivative instruments																		$ 300,000
March 2025 Private Placement
Class of Stock [Line Items]
Aggregate principal amount										$ 3,400,000
Offering expenses								$ 1,400,000
Warrant issuance expenses								1,000,000
Fair value								13,200,000
Fair value of warrant liability reclassified to equity								5,800,000
Percentage agreed to repay purchasers holding securities						115.00%
Percentage of proceeds to repay purchasers from capital raised						90.00%
March 2025 Private Placement | Exchange [Member]
Class of Stock [Line Items]
Aggregate principal amount									$ 3,200,000
March 2025 Private Placement | Private Placement Share [Member]
Class of Stock [Line Items]
Purchase price of share | $ / shares						$ 0.66
Shares returned and cancelled | shares															3,472,740			3,472,740
Paid purchasers to returened shares															$ 2,300,000			$ 2,300,000
March 2025 Private Placement | Prefunded Warrant [Member]
Class of Stock [Line Items]
Number of securities called by warrant or right | shares						10,633,650
Purchase price of share | $ / shares						$ 0.659
March 2025 Private Placement | Private Placement And Prefunded Warrant [Member]
Class of Stock [Line Items]
Number of shares agreed to return | shares						12,241,986
March 2025 Private Placement | Series A Warrant [Member] | New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued | shares									22,727,270
March 2025 Private Placement | Series A Warrant [Member] | Exchange [Member]
Class of Stock [Line Items]
Number of shares issued | shares									5,314,870
March 2025 Private Placement | Series A Warrant [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued | shares									28,042,138
March 2025 Private Placement | Series B Warrant [Member] | New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued | shares									22,727,270
March 2025 Private Placement | Series B Warrant [Member] | Exchange [Member]
Class of Stock [Line Items]
Number of shares issued | shares									5,314,870
March 2025 Private Placement | Series B Warrant [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued | shares									28,042,138
March 2025 Private Placement | Pre-Funded Warrants [Member] | New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued | shares									19,650,000
March 2025 Private Placement | Pre-Funded Warrants [Member] | Exchange [Member]
Class of Stock [Line Items]
Number of shares issued | shares									4,322,400
March 2025 Private Placement | Pre-Funded Warrants [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Number of shares issued | shares									23,972,400
March 2025 Private Placement | Series A Warrant and Series B Warrant [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Class of warrant outstanding | shares															2,611,809			2,611,809
March 2025 Private Placement | Common Stock [Member]
Class of Stock [Line Items]
Proceeds from private placement								15,000,000
Maximum beneficial ownership percentage									4.99%
Maximum beneficial ownership percentage by election of holder									9.99%
Offering expenses								$ 400,000
March 2025 Private Placement | Common Stock [Member] | New Capital Subscriptions [Member]
Class of Stock [Line Items]
Number of shares issued | shares									3,077,270
March 2025 Private Placement | Common Stock [Member] | Exchange [Member]
Class of Stock [Line Items]
Number of shares issued | shares									992,468
March 2025 Private Placement | Common Stock [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares									$ 0.001
Number of shares issued | shares									4,069,738
Issue and sale of share | shares									28,042,140
March 2025 Private Placement | Common Stock [Member] | Private Placement Share [Member]
Class of Stock [Line Items]
Purchase price of share | $ / shares									$ 0.66
March 2025 Private Placement | Common Stock [Member] | Prefunded Warrant [Member]
Class of Stock [Line Items]
Purchase price of share | $ / shares									0.659
March 2025 Private Placement | Common Stock [Member] | Series A Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares									1.32
Floor price | $ / shares									$ 0.132
Expiration period									5 years
March 2025 Private Placement | Common Stock [Member] | Series B Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares									$ 1.98
Expiration period									2 years 6 months
March 2025 Private Placement | Exchange Notes
Class of Stock [Line Items]
Fair value									$ 3,500,000
May 2024 Private Placement
Class of Stock [Line Items]
Financing expense														$ 3,500,000
Change in fair value of warrants																				$ 5,700,000
May 2024 Private Placement | Common Stock [Member]
Class of Stock [Line Items]
Proceeds from private placement												$ 7,300,000
Number of shares issued | shares												1,439,988
Offering expenses												$ 400,000
Proceeds from issuance of warrants														$ 10,900,000
May 2024 Private Placement | Common Stock [Member] | Securities Purchase Agreement [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares														$ 0.001
Issue and sale of share | shares														3,591,532
May 2024 Private Placement | Common Stock [Member] | Private Placement And Prefunded Warrant [Member] | Initial Subscription [Member]
Class of Stock [Line Items]
Purchase price of share | $ / shares														$ 2.022
May 2024 Private Placement | Common Stock [Member] | Private Placement And Prefunded Warrant [Member] | Additional Subscription [Member]
Class of Stock [Line Items]
Purchase price of share | $ / shares														$ 2.158
May 2024 Private Placement | Common Stock [Member] | Series A Warrant [Member]
Class of Stock [Line Items]
Number of shares issued | shares												3,591,532		3,591,532
May 2024 Private Placement | Common Stock [Member] | Series A Warrant [Member] | Initial Subscription [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares														$ 1.772
May 2024 Private Placement | Common Stock [Member] | Series B Warrant [Member]
Class of Stock [Line Items]
Number of shares issued | shares												3,591,532		3,591,532
May 2024 Private Placement | Common Stock [Member] | Series B Warrant [Member] | Additional Subscription [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares														$ 1.908
May 2024 Private Placement | Common Stock [Member] | Pre-Funded Warrants [Member]
Class of Stock [Line Items]
Number of shares issued | shares												2,151,544
May 2024 Private Placement | Common Stock [Member] | Series A Warrant and Series B Warrant [Member]
Class of Stock [Line Items]
Warrant exercise price (in dollars per share) | $ / shares														1.79
May 2024 Private Placement | Common Stock [Member] | Series A Warrant and Series B Warrant [Member] | Initial Subscription [Member]
Class of Stock [Line Items]
Closing price per share | $ / shares														$ 2.04
March 2025 Series A Warrants
Class of Stock [Line Items]
Fair value																								$ 5,000,000
Change in fair value of warrants																		$ 2,700,000
Extinguishment of Warrants																		2,300,000
March 2025 Series B Warrants [Member]
Class of Stock [Line Items]
Number of securities called by warrant or right | shares					34,794,540	35,536,380
Warrant exercise price (in dollars per share) | $ / shares						$ 1.98
Change in fair value of warrants							$ 3,800,000
Fair value of warrant liability reclassified to equity						$ 11,000,000
Remeasurement of warrant liability						$ 4,500,000
Cashless warrants excercised for common stock | shares					34,794,540
Warrants exercise ratio						1																3
Lincoln Park Purchase Agreement | Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Common stock, par value (in dollars per share) | $ / shares						$ 0.001
Maximum obligation under single regular purchase				$ 1,000,000
Legal fees																		$ 50,000
Lincoln Park Purchase Agreement | Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member]
Class of Stock [Line Items]
Issue and sale of share | shares	1,612,903																	44,575,496
Period exercisable from the date of issuance																		36 months
Initial commitment fee paid in cash						$ 500,000
Additional commitment fee paid in cash						500,000
Maximum value of shares to be issued under agreement						50,000,000
Number of maximum common shares can be resale | shares															50,000,000			50,000,000
Regular purchase price per share threshold percentage				97.00%
Consecutive business days | BusinessDay				10
Accelerated purchase price per share threshold percentage				96.50%
Additional accelerated purchase price per share threshold percentage				96.50%
Aggregate gross proceeds from sales of common stock						$ 25,000,000												$ 19,600,000
Lincoln Park Purchase Agreement | Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member] | Closing Stock Price Not Below $0.10 [Member]
Class of Stock [Line Items]
Issue and sale of share | shares				300,000
Closing price per share | $ / shares				$ 0.1
Lincoln Park Purchase Agreement | Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member] | Closing Stock Price Not Below $0.50 [Member]
Class of Stock [Line Items]
Issue and sale of share | shares				400,000
Closing price per share | $ / shares				$ 0.5
Lincoln Park Purchase Agreement | Common Stock [Member] | Lincoln Park Capital Fund, LLC [Member] | Closing Stock Price Not Below $0.75 [Member]
Class of Stock [Line Items]
Issue and sale of share | shares				500,000
Closing price per share | $ / shares				$ 0.75

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Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 505
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 4
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481520/505-30-50-4

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 815
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 8A
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480434/815-10-50-8A

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
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