iAnthus Capital Holdings, Inc. Quarterly report [Sections 13 or 15(d)]

Quarterly report [Sections 13 or 15(d)]

Contingencies And Guarantees - Additional Information (Detail)

Contingencies And Guarantees - Additional Information (Detail) - USD ($) shares in Thousands, $ in Thousands											36 Months Ended
	Sep. 11, 2026	Jan. 05, 2026	Sep. 19, 2025	Aug. 20, 2025	Aug. 08, 2025	Jun. 15, 2025	Jun. 04, 2025	Aug. 19, 2021	Aug. 23, 2019	Apr. 24, 2019	Jan. 05, 2029	Sep. 30, 2026	Dec. 31, 2025
Contingencies And Guarantees [Line Items]
Loss contingency plaintiffs value						$ 5,500
Loss Contingency, Settlement Agreement, Court						(i) $1,250,000 within five (5) business days of executing the Roberts Settlement Agreement; (ii) $150,000 on January 5, 2026; and (iii) starting January 5, 2026, $4,100,000 in equal monthly installments over thirty-six (36) months, bearing a simple interest rate of 6% per year. On June 16, 2025, the parties filed a Joint Stipulation to Dismiss this matter with prejudice, which was approved by the court on June 17, 2025.
Claim for alleged payments										$ 1,300
Disputed Debentures And Related Indenture Amount										111,000
Breach Of Security Subordination Agreement Amount										$ 3,500
Damages For Breach Of Consultancy Agreement							$ 400
Damages For Breach Of Consultancy Agreement Plus Certain Warrants							200
Damages For Breach Of The Duty Of Good Faith							1,000
Breach Of The Disputed Debentures And Indentures And Breach Of Fiduciary Obligations							$ 1,800
Common stock, shares, issued												6,974,812	6,859,128
William Huber [Member]
Contingencies And Guarantees [Line Items]
Breach Of Security Subordination Agreement Amount									$ 3,500
Damages For Breach Of Consultancy Agreement									400
Damages For Breach Of Consultancy Agreement Plus Certain Warrants									200
Damages For Breach Of The Duty Of Good Faith									1,000
Breach Of The Disputed Debentures And Indentures And Breach Of Fiduciary Obligations									$ 111,000
Maximum [Member]
Contingencies And Guarantees [Line Items]
Total Damages Sought Value								$ 10,000
Minimum [Member]
Contingencies And Guarantees [Line Items]
Total Damages Sought Value								$ 1,000
Settlement Agreement [Member]
Contingencies And Guarantees [Line Items]
Payments for Legal Settlements			$ 1,700	$ 300	$ 2,000
Subordination Agreement [Member]
Contingencies And Guarantees [Line Items]
Breach Of Security Subordination Agreement Amount	$ 800
Roberts Settlement Agreement [Member]
Contingencies And Guarantees [Line Items]
Loss contingency plaintiffs value		$ 150				$ 1,250					$ 4,100
Simple interest rate											6.00%