v3.21.2

Stockholder's equity - Authorized (Details)	9 Months Ended	12 Months Ended
Stockholder's equity - Authorized (Details)	Sep. 30, 2021	Dec. 31, 2020
Common Stock, shares authorized	Unlimited	Unlimited
Common Shares
Common Stock, shares authorized	Unlimited	Unlimited
Class B Shares
Common Stock, shares authorized	Unlimited	Unlimited
Stock conversion ratio	1
First Preferred Shares
Preferred Stock, shares authorized	Unlimited	Unlimited
Series I preferred shares
Preferred Stock, shares authorized	Unlimited	Unlimited
Stock conversion ratio	30
Limitation on conversion, beneficial ownership percentage	4.99%
Series II preferred shares
Preferred Stock, shares authorized	Unlimited	Unlimited
Stock conversion ratio	1
Limitation on conversion, period of notice	61 days
Conversion limitation, holder ownership percentage	9.99%
Conversion limitation, holder ownership percentage, personal information form	19.99%
Conversion limitation, holder ownership percentage, Toronto Stock Exchange and shareholder approval	19.99%

The beneficial ownership percentage which can not be exceeded when converting one class of stock into common shares.

+ References

No definition available.

+ Details

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- Definition

The period of time which the holder must provide written notice in order to exceed the beneficial ownership percentage limitation upon conversion of stock.

+ References

No definition available.

+ Details

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- Definition

The limit to which the beneficial ownership percentage limitation on conversion can be raised without involvement of the Toronto Stock Exchange.

+ References

No definition available.

+ Details

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- Definition

Beneficial ownership percentage threshold which requires approval of Toronto Stock Exchange and shareholders.

+ References

No definition available.

+ Details

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- Definition

The limit to which the beneficial ownership percentage limitation on conversion can be raised by clearance of a personal information form submitted to the Toronto Stock Exchange.

+ References

No definition available.

+ Details

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- Definition

Ratio applied to the conversion of one class of shares to another class of shares.

+ References

No definition available.

+ Details

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Data Type:	xbrli:pureItemType
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- Definition

Indicates that the number of common shares permitted to be issued by an entity's charter and bylaws is unlimited. The acceptable value is "Unlimited".

+ 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 210.5-02.29)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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- Definition

Indicates that the number of nonredeemable preferred shares, or preferred stock redeemable solely at the option of the issuer, permitted to be issued by an entity's charter and bylaws is unlimited. The acceptable value is "Unlimited".

+ 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 210.5-02.28)
-URI http://asc.fasb.org/extlink&oid=120391452&loc=d3e13212-122682

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Trillium Therapeutics Inc. 10-Q