CONDENSED CONSOLIDATED INTERIM STATEMENTS OF CHANGES IN STOCKHOLDERS' EQUITY (unaudited) - USD ($) $ in Thousands	Total	Total 4Front Ventures Corp. Shareholders' Equity	Share Capital	Additional Paid-In Capital	Deficit	Non-Controlling Interest
Beginning balance (in shares) at Dec. 31, 2021			594,181,604
Beginning balance at Dec. 31, 2021	$ 37,532	$ 37,460	$ 274,120	$ 52,197	$ (288,857)	$ 72
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Shares issued for NECC pursuant to acquisition (in shares			28,571,428
Shares issued for NECC pursuant to acquisition	17,689	17,689	$ 17,689
Share-based compensation	1,038	1,038		1,038
Conversion of notes to equity (in shares)			6,235,512
Conversion of notes to equity	3,122	3,122	$ 3,122
Shares issued with exercise of warrants (in shares)			88,659
Shares issued with exercise of warrants	50	50	$ 50
Net loss	(5,894)	(5,899)			(5,899)	5
Ending balance (in shares) at Mar. 31, 2022			629,077,203
Ending balance at Mar. 31, 2022	$ 53,537	53,460	$ 294,981	53,235	(294,756)	77
Beginning balance (in shares) at Dec. 31, 2022	643,416,275		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]
Shares issued for NECC pursuant to acquisition	0
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		643,416,275
Ending balance at Mar. 31, 2023	$ 17,979	$ 17,881	$ 304,602	$ 60,431	$ (347,152)	$ 98