iAnthus Capital Holdings, Inc. Quarterly report pursuant to Section 13 or 15(d)

Quarterly report pursuant to Section 13 or 15(d)

Long-Term Debt - Additional Information (Detail)

Long-Term Debt - Additional Information (Detail) $ / shares in Units, $ in Thousands										3 Months Ended		9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares	Feb. 02, 2021 USD ($)	Jul. 13, 2020 USD ($)	Dec. 29, 2019	Sep. 30, 2019 USD ($)	May 02, 2019 USD ($) $ / shares shares	Mar. 18, 2019 USD ($) $ / shares shares	Feb. 05, 2019 USD ($)	May 14, 2018 USD ($) $ / shares	Sep. 30, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($)	Sep. 30, 2021 USD ($) $ / shares	Sep. 30, 2020 USD ($)	Apr. 04, 2021 USD ($)	Mar. 31, 2021 USD ($)	Dec. 31, 2020 USD ($) $ / shares	Dec. 20, 2019 USD ($)
Debt Instrument [Line Items]
Interest expense										$ 400	$ 400	$ 1,300	$ 1,200
Accretion expense										767	4,354	8,283	12,471
Long term debt default amount principal	$ 97,500									97,500		97,500
Secured debt long term fair value	231,971									231,971		231,971				$ 189,363
Unamortized debt issuance costs	$ 2,800									$ 2,800		$ 2,800				$ 3,500
Class of warrants or rights exercise price per share \| $ / shares	$ 3.57									$ 3.57		$ 3.57				$ 4.06
Cash balance	$ 19,502									$ 19,502		$ 19,502				$ 11,015
Payment In Kind [Member]
Debt Instrument [Line Items]
Percentage of total interest that can be paid through cash or in kind route							50.00%
Private Placement [Member] \| March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Interest rate on secured notes	8.00%									8.00%		8.00%
Debt instrument terms of interest payment							payable quarterly
Class of warrants or rights number of shares covered by warrants or rights \| shares							2,177,291
Class of warrants or rights exercise price per share \| $ / shares							$ 6.43
Class of warrant or rights expiry date						Mar. 15, 2022
Private Placement [Member] \| May 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Debt instrument maturity date						Mar. 15, 2023
Debt instrument terms of interest payment						payable quarterly
Class of warrants or rights number of shares covered by warrants or rights \| shares						1,555,207
Class of warrants or rights exercise price per share \| $ / shares						$ 6.43
Private Placement [Member] \| In Cash [Member] \| March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Percentage of total interest that can be paid through cash or in kind route							50.00%
Private Placement [Member] \| Payment In Kind [Member] \| March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Percentage of total interest that can be paid through cash or in kind route							50.00%
iAnthus New Jersey, LLC [Member]
Debt Instrument [Line Items]
Description about qualified financing												“Qualified Financing” means a transaction or series of related transactions resulting in net proceeds to the Company of not less than $10 million from the subscription of the Company’s securities, including, but not limited to, a private placement or rights offering.
Threshold limit of qualified financing, net proceeds not less than the subscription of securities												$ 10,000
Secured Debt [Member]
Debt Instrument [Line Items]
Long term debt exit fee payable	$ 10,000									$ 10,000		10,000
Secured Debt [Member] \| Tranche One [Member]
Debt Instrument [Line Items]
Debt instrument face value									$ 40,000
Debt instrument maturity date									May 14, 2021
Interest rate on secured notes									16.00%
Debt instrument conversion price per share \| $ / shares									$ 3.08
Debt instrument beneficial conversion feature	7,900
Interest expense										1,700	1,700	5,000	4,700
Accretion expense										0	1,500	2,400	4,400
Long term debt default amount principal											10,300		10,300	$ 60,000	$ 97,500
Long term debt default amount accrued interest	3,000									3,000		3,000		$ 8,400	$ 26,900
Long term debt exit fee payable principal and interest	15,000									15,000	13,300	15,000	13,300
Long term debt exit fee payable	10,300									10,300	10,300	10,300	10,300
Interest expenses incurred on exit fees										4,700	3,000
Interest payable on exit fee	$ 4,700									$ 4,700	3,000	$ 4,700	3,000
Debt instrument financial covenant description												The terms also contain a financial covenant requiring the Company’s asset value to be 1.75 times the total net debt at each quarter end and maintain a minimum cash balance of $1.0 million while the Tranche One Secured Notes remain outstanding (the “market value test”).
Financial covenant requires to maintain ratio of asset value to net debt	1.75									1.75		1.75
Cash balance	$ 1,000									$ 1,000		$ 1,000
Secured Debt [Member] \| Tranche One [Member] \| Accretion Expense [Member]
Debt Instrument [Line Items]
Amortization of debt discount										0	700	1,000	2,000
Secured Debt [Member] \| Tranche Two [Member]
Debt Instrument [Line Items]
Debt instrument face value					$ 20,000
Debt instrument maturity date					May 14, 2021
Interest rate on secured notes					13.00%
Interest expense										800	800	2,400	2,300
Accretion expense										0	500	700	1,400
Secured Debt [Member] \| Tranche Three [Member]
Debt Instrument [Line Items]
Debt instrument face value																	$ 36,200
Debt instrument maturity date				May 14, 2021
Interest rate on secured notes																	13.00%
Interest expense										1,500	1,500	4,400	4,100
Accretion expense										0	1,000	1,600	3,000
Secured Debt [Member] \| Tranche Four [Member]
Debt Instrument [Line Items]
Debt instrument face value			$ 14,700
Debt instrument maturity date			Jul. 13, 2025
Interest expense										300	300	900	300
Accretion expense										100	100	300	100
Debt instrument original issue discount percentage			8.00%
Escrow deposit	0									0		0				400
iAnthus New Jersey, LLC Senior Secured Bridge Notes [Member] \| iAnthus New Jersey, LLC [Member]
Debt Instrument [Line Items]
Debt instrument face value		$ 11,000
Debt instrument maturity date		Feb. 02, 2023
Interest rate on secured notes		14.00%
Interest expense										400	0	1,000	0
Accretion expense										100	$ 0	200	$ 0
Secured debt long term fair value		$ 10,300
Unamortized debt issuance costs		$ 700
Escrow deposit	$ 4,100									4,100		4,100				$ 0
iAnthus New Jersey, LLC Senior Secured Bridge Notes [Member] \| Prospective Recapitalization Transaction [Member] \| iAnthus New Jersey, LLC [Member]
Debt Instrument [Line Items]
Interest rate on secured notes		8.00%
iAnthus New Jersey, LLC Senior Secured Bridge Notes [Member] \| Prospective Default [Member] \| iAnthus New Jersey, LLC [Member]
Debt Instrument [Line Items]
Interest rate on secured notes		25.00%
March 2019 Debentures [Member] \| Private Placement [Member]
Debt Instrument [Line Items]
Debt instrument face value							$ 35,000
Debt instrument maturity date							Mar. 15, 2023
Interest rate on secured notes					8.00%						8.00%		8.00%
Interest expense										700	$ 700	2,100	$ 2,100
Accretion expense										$ 400	$ 400	$ 1,100	$ 1,100
March 2019 Debentures [Member] \| Private Placement [Member] \| In Cash [Member]
Debt Instrument [Line Items]
Percentage of total interest that can be paid through cash or in kind route							50.00%
May 2019 Debentures [Member] \| Private Placement [Member]
Debt Instrument [Line Items]
Debt instrument face value						$ 25,000
Interest rate on secured notes	8.00%									8.00%	8.00%	8.00%	8.00%
Interest expense										$ 500	$ 200	$ 1,500	$ 1,500
Accretion expense										$ 200		$ 600	$ 600
May 2019 Debentures [Member] \| Private Placement [Member] \| Payment In Kind [Member]
Debt Instrument [Line Items]
Percentage of total interest that can be paid through cash or in kind route							50.00%
Stavola Trust Note [Member]
Debt Instrument [Line Items]
Debt instrument maturity date								Jan. 19, 2020
Business combination liablity assumed non current debt								$ 10,800
Related party transaction rate of interest								8.00%