CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN SHAREHOLDERS' (DEFICIT) EQUITY (unaudited) - USD ($) $ in Thousands	Total	Total 4Front Ventures Corp. Shareholders' Equity	Common Stock	Additional Paid-In Capital	Deficit	Non-Controlling Interest
Beginning balance (in shares) at Dec. 31, 2022			643,416,275
Beginning balance at Dec. 31, 2022	$ 28,351	$ 28,258	$ 304,602	$ 59,411	$ (335,755)	$ 93
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Share-based compensation	1,020	1,020		1,020
Net loss	(11,392)	(11,397)			(11,397)	5
Ending balance (in shares) at Mar. 31, 2023			643,416,275
Ending balance at Mar. 31, 2023	$ 17,979	17,881	$ 304,602	60,431	(347,152)	98
Beginning balance (in shares) at Dec. 31, 2023	669,519,349		669,519,349
Beginning balance at Dec. 31, 2023	$ (51,394)	(51,502)	$ 308,952	66,948	(427,402)	108
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Conversion of debt to equity (in shares)			244,680,852
Conversion of debt to equity	28,270	28,270	$ 28,270	0
Share-based compensation	1,008	1,008		1,008
Net loss	$ (18,453)	(18,453)			(18,453)
Ending balance (in shares) at Mar. 31, 2024	914,200,201		914,200,201
Ending balance at Mar. 31, 2024	$ (40,569)	$ (40,677)	$ 337,222	$ 67,956	$ (445,855)	$ 108