Supplementary Cash Flow Information - Summary of Changes in Non-Cash Working Capital (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2022	Mar. 31, 2021
Changes in operating assets and liabilities
Accounts receivable and other receivables	$ (2,309)	$ 100
Inventory	(3,823)	(934)
Prepaid expenses	153	(830)
Deposits	257	(460)
Accounts payable and accrued liabilities	778	1,393
Taxes payable	3,651	1,806
Equity attributable to 4Front Ventures Corp.	$ (1,293)	$ 1,075

Increase decrease in equity attributable.

No definition available.

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- Definition

The increase (decrease) during the reporting period in the amount due from customers for the credit sale of goods and services; includes accounts receivable and other types of receivables.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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- Definition

The increase (decrease) during the reporting period in the amounts payable to vendors for goods and services received and the amount of obligations and expenses incurred but not paid.

+ References

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- Definition

The increase (decrease) during the reporting period of all taxes owed but not paid, including income, property and other taxes.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3602-108585

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- Definition

The net cash inflow or outflow for the increase (decrease) in the beginning and end of period deposits balances.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 8
-URI http://asc.fasb.org/extlink&oid=123570139&loc=d3e3095-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 230
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=123398031&loc=d3e60009-112784

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- Definition

The increase (decrease) during the reporting period in the aggregate value of all inventory held by the reporting entity, associated with underlying transactions that are classified as operating activities.

+ References

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- References

No definition available.

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- Definition

The increase (decrease) during the reporting period in the amount of outstanding money paid in advance for goods or services that bring economic benefits for future periods.

+ References

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