Long-Term Debt - Additional Information (Detail)

v3.22.0.1

Long-Term Debt - Additional Information (Detail) $ / shares in Units, $ in Thousands										12 Months Ended
	Dec. 31, 2021 USD ($) Customer $ / shares shares		Feb. 02, 2021 USD ($)	Jul. 13, 2020 USD ($)	Dec. 20, 2019 USD ($) Customer shares $ / shares	Sep. 30, 2019 USD ($) shares $ / shares	May 02, 2019 USD ($) $ / shares shares	Mar. 18, 2019 USD ($) $ / shares shares	May 14, 2018 USD ($) $ / shares	Dec. 31, 2021 USD ($) Customer $ / shares shares		Dec. 31, 2020 USD ($) $ / shares		Jan. 07, 2022 USD ($) shares	Apr. 04, 2021 USD ($)	Mar. 31, 2021 USD ($)	Jul. 10, 2020	Dec. 31, 2019 USD ($)
Debt Instrument [Line Items]
Debt Instrument, Convertible, Number of Equity Instruments | Customer										4,222,971
Debt instrument, convertible, conversion price | $ / shares	$ 5.92									$ 5.92
Volume weighted average trading price | $ / shares	$ 10.29									$ 10.29
Interest expense										$ 1,700		$ 3,400
Accretion expense										9,057		16,962
Long term debt default amount principal	$ 97,500									97,500
Long term debt exit fee payable principal and interest	15,400									15,400		13,800
Long term debt exit fee payable	10,300									10,300
Interest expenses incurred on exit fees										5,100
Secured debt long term fair value	242,104									242,104		189,363
Unamortized debt issuance costs	$ 2,500									$ 2,500		$ 3,500
Exercise price of warrants | $ / shares	$ 3.56					$ 1.97				$ 3.56		$ 4.06
Fair value of warrants, net of issuance costs	$ 100									$ 100		$ 200
Warrants and rights outstanding, measurement input	77.97									77.97
Debt issuance costs										$ 694		2,230
Debt instrument, interest rate																	16.00%
Long-term debt	$ 193,380									193,380		$ 171,175						$ 142,052
Measurement Input, Price Volatility [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input												85.0
Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input												0.0
Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input												0.6
March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Debt instrument maturity date							Mar. 15, 2023
Warrants and Rights Outstanding, Maturity Date							Mar. 15, 2022
Fair value of warrants, net of issuance costs	4,500									$ 4,500
Warrant issuance cost	$ 1,300
March 2019 Equity Warrants [Member] | Measurement Input, Price Volatility [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	74.7									74.7
March 2019 Equity Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	0.0									0.0
March 2019 Equity Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	2.4									2.4
May 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Debt instrument terms of interest payment							payable quarterly
Fair value of warrants, net of issuance costs	$ 2,600									$ 2,600
Warrant issuance cost	$ 400
May 2019 Equity Warrants [Member] | Measurement Input, Price Volatility [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input | Customer	73.6									73.6
May 2019 Equity Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input | Customer	0.0									0.0
May 2019 Equity Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input | Customer	2.3									2.3
Private Placement [Member] | March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Interest rate on secured notes	8.00%									8.00%
Class of warrant or right, number of securities called by warrants or rights | shares								2,177,291
Exercise price of warrants | $ / shares								$ 6.43
Private Placement [Member] | May 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, number of securities called by warrants or rights | shares							1,555,207
Exercise price of warrants | $ / 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%
iAnthus New Jersey LLC
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
Tranche One [Member]
Debt Instrument [Line Items]
Debt instrument, fair value disclosure									$ 26,200
Long-term debt									2,300
Tranche One [Member] | Common Class A [Member]
Debt Instrument [Line Items]
Issuance Costs										$ 4,400
Tranche One [Member] | Measurement Input, Price Volatility [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	88.3									88.3
Tranche One [Member] | Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	0.0									0.0
Tranche One [Member] | Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	2.0									2.0
Tranche One [Member] | Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, date from which warrants or rights exercisable										May 14, 2021
Tranche Two [Member]
Debt Instrument [Line Items]
Debt instrument, fair value disclosure						$ 17,300
Long-term debt						300
Tranche Two [Member] | Tranche Two Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, date from which warrants or rights exercisable										May 14, 2021
Tranche Two [Member] | Tranche Two Equity Warrants [Member] | Common Class A [Member]
Debt Instrument [Line Items]
Issuance Costs										$ 300
Tranche Two [Member] | Tranche Two Equity Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	0.0									0.0
Tranche Two [Member] | Tranche Two Equity Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	1.6									1.6
Tranche Three [Member]
Debt Instrument [Line Items]
Debt instrument, fair value disclosure					$ 30,900
Tranche Three [Member] | Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, date from which warrants or rights exercisable										May 14, 2021
Tranche Three [Member] | Equity Warrants [Member] | Common Class A [Member]
Debt Instrument [Line Items]
Issuance Costs										$ 700
Tranche Three [Member] | Equity Warrants [Member] | Measurement Input, Price Volatility [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	74.6									74.6
Tranche Three [Member] | Equity Warrants [Member] | Measurement Input, Expected Dividend Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	0.0									0.0
Tranche Three [Member] | Equity Warrants [Member] | Measurement Input, Risk Free Interest Rate [Member]
Debt Instrument [Line Items]
Warrants and rights outstanding, measurement input	1.7									1.7
Secured Debt [Member]
Debt Instrument [Line Items]
Long term debt exit fee payable	$ 10,000									$ 10,000
Long-term debt	134,902	[1]								134,902	[1]	$ 115,350	[1]					77,248
Secured Debt [Member] | Tranche One [Member]
Debt Instrument [Line Items]
Debt instrument face value									$ 40,000
Debt instrument maturity date									May 14, 2021
Debt instrument, convertible, conversion price | $ / shares									$ 3.08
Amortization of debt discount										1,000		2,600
Debt instrument beneficial conversion feature									$ 7,900
Interest expense										6,700		6,400
Accretion expense										2,400		6,000
Long term debt default amount principal												10,300			$ 60,000	$ 97,500
Long term debt default amount accrued interest	$ 3,500									$ 3,500					$ 9,600	$ 30,900
Percentage of total outstanding debt instrument including accrued and unpaid interest and fees									105.00%
Percentage of total outstanding debt instrument principal amount									90.00%
Secured Debt [Member] | Tranche One [Member] | Common Class A [Member]
Debt Instrument [Line Items]
Class of warrant or right, number of securities called by warrants or rights | shares	3,891,051									3,891,051
Exercise price of warrants | $ / shares	$ 3.86									$ 3.86
Debt instrument, fair value disclosure	$ 8,600									$ 8,600
Warrants and rights outstanding, measurement input	4,800,000									4,800,000
Class of warrant or right, date from which warrants or rights exercisable										May 14, 2021
Class of warrant or right, Issued	$ 10,000									$ 10,000
Common stock, conversion basis										one
Shares issued, price per share | $ / shares	$ 2.57									$ 2.57
Class of warrant or right, number of securities called by each warrant or right | shares	1									1
Secured Debt [Member] | Tranche One [Member] | Minimum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate									3.00%
Secured Debt [Member] | Tranche One [Member] | Maximum [Member]
Debt Instrument [Line Items]
Debt instrument, interest rate									16.00%
Secured Debt [Member] | Tranche One [Member] | Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, number of securities called by warrants or rights | shares	6,670,372									6,670,372
Exercise price of warrants | $ / shares	$ 3.60									$ 3.60
Warrants and rights outstanding, measurement input | Customer	8,400,000									8,400,000
Class of warrant or right, date from which warrants or rights exercisable										May 14, 2021
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										$ 3,200		3,100
Accretion expense										$ 700		1,800
Warrants and rights outstanding, measurement input	16.0									16.0
Secured Debt [Member] | Tranche Two [Member] | Tranche Two Equity Warrants [Member]
Debt Instrument [Line Items]
Class of warrant or right, number of securities called by warrants or rights | shares						5,076,142
Warrants and rights outstanding, measurement input | Customer	2,600,000									2,600,000
Class of warrant or right, date from which warrants or rights exercisable						May 14, 2021
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										$ 5,900		5,600
Accretion expense										$ 1,600		4,100
Warrants and rights outstanding, measurement input	16.0									16.0
Secured Debt [Member] | Tranche Three [Member] | Equity Warrants [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Number of Equity Instruments | shares					22,448,415
Debt instrument, convertible, conversion price | $ / shares					$ 1.61
Class of warrant or right, number of securities called by warrants or rights | shares					10,792,508
Exercise price of warrants | $ / shares					$ 1.67
Warrants and rights outstanding, measurement input | Customer					5,100,000
Class of warrant or right, date from which warrants or rights exercisable					May 14, 2021
Issuance Costs					$ 600
Secured Debt [Member] | Tranche Four [Member]
Debt Instrument [Line Items]
Debt instrument face value				$ 14,700
Debt instrument maturity date				Jul. 13, 2025
Interest rate on secured notes				8.00%
Interest expense										$ 1,300		600
Accretion expense										400		200
Debt instrument original issue discount percentage				5.00%
Escrow deposit	$ 0									0		400
Secured Debt [Member] | Tranche Four [Member] | Prospective Default [Member] | Minimum [Member]
Debt Instrument [Line Items]
Interest rate on secured notes				8.00%
Secured Debt [Member] | Tranche Four [Member] | Prospective Default [Member] | Maximum [Member]
Debt Instrument [Line Items]
Interest rate on secured notes				16.00%
Secured Debt [Member] | Tranche Two Conversion Option [Member] | Tranche Two Equity Warrants [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Number of Equity Instruments | shares						10,582,011
Debt instrument, convertible, conversion price | $ / shares						$ 1.89
New Jersey Senior Secured Bridge Notes [Member] | iAnthus New Jersey LLC
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										1,500		0
Accretion expense										300		0
Secured debt long term fair value	12,500		$ 10,300							12,500
Unamortized debt issuance costs	2,200		$ 700							2,200
Escrow deposit	$ 3,300									$ 3,300		0
New Jersey Senior Secured Bridge Notes [Member] | Prospective Recapitalization Transaction [Member] | iAnthus New Jersey LLC
Debt Instrument [Line Items]
Interest rate on secured notes			8.00%
New Jersey Senior Secured Bridge Notes [Member] | Prospective Default [Member] | iAnthus New Jersey LLC
Debt Instrument [Line Items]
Interest rate on secured notes			25.00%
March 2019 Debentures [Member]
Debt Instrument [Line Items]
Volume weighted average trading price | $ / shares	$ 10.29									$ 10.29
Unamortized debt issuance costs	$ 1,200									$ 1,200
Debt instrument, fair value disclosure	30,300									30,300
Debt instrument fees	$ 1,300									$ 1,300
Debt instrument fee issued in common shares | shares	700,000									700,000
Debt issuance costs	$ 600
Long-term debt	$ 33,138									$ 33,138		31,665						30,255
March 2019 Debentures [Member] | March 2019 Equity Warrants [Member]
Debt Instrument [Line Items]
Debt Instrument, Convertible, Number of Equity Instruments | Customer	5,912,159
Debt instrument, convertible, conversion price | $ / shares	$ 5.92									$ 5.92
March 2019 Debentures [Member] | Private Placement [Member]
Debt Instrument [Line Items]
Debt instrument face value								$ 35,000
Debt instrument maturity date								Mar. 15, 2023
Debt instrument terms of interest payment								payable quarterly
Interest expense										$ 2,800		2,800
Accretion expense										1,500		1,400
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]
Debt Instrument [Line Items]
Unamortized debt issuance costs	$ 400									400
Debt instrument, fair value disclosure	22,300									22,300
Debt instrument fees														$ 400
Debt instrument fee issued in common shares | shares														100,000
Debt issuance costs	300
Long-term debt	$ 24,033									$ 24,033		23,240						22,471
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%
Interest expense										$ 2,000		2,000
Accretion expense										800		$ 800
Stavola Trust Note [Member]
Debt Instrument [Line Items]
Debt instrument maturity date	Jan. 19, 2020
Business combination liablity assumed non current debt	$ 10,800									$ 10,800
Related party transaction rate of interest	8.00%
Long-term debt																		$ 10,800
[1] This amount includes the Company’s obligation to pay an exit fee of $10.0 million that accrues interest at a rate of 13% per annum (the “Exit Fee”) under the Secured Notes.