Notes Payable - Additional Information (Detail) - USD ($)			9 Months Ended
Aug. 20, 2020	Jun. 05, 2020	Sep. 30, 2020	Dec. 31, 2017
Mortgage Loans	$ 833,000	$ 1,814,000
Mortage loan interest rate	7.25%	5.00%		2.17%
Maturity date	Aug. 20, 2025	Jun. 05, 2035
Debt held by related parties			1.00%
Debt held by unrelated third-parties			99.00%
Warrant
Warrants issued		35,000
Warrants issued, Value		$ 181,272

Debt Percentage Held By Related Parties

No definition available.

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- Definition

Debt Percentage Held By UnRelated Third Parties

+ References

No definition available.

+ Details

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- Definition

Stock issued during period shares warrants issued.

+ References

No definition available.

+ Details

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- Definition

Stock issued during period value warrants issued.

+ References

No definition available.

+ Details

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Namespace Prefix:	gtbif_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

+ Details

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Data Type:	num:percentItemType
Balance Type:	na
Period Type:	instant

- Definition

Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM-DD format.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(2))
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

The aggregate amount of the participating mortgage obligation at the end of the accounting period.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 470
-SubTopic 30
-Section 50
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=99377297&loc=d3e10013-112621

+ Details

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Period Type:	instant

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