Class of Warrant or Right, Threshold Consecutive Trading Days

No definition available.

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- Definition

Number Of Ordinary Shares Conversion Ratio

+ References

No definition available.

+ Details

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- Definition

Proceeds from Warrant Exercises, Fully Exercised

+ References

No definition available.

+ Details

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Namespace Prefix:	cmps_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

Sale Of Stock, Amount Authorized

+ References

No definition available.

+ Details

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Namespace Prefix:	cmps_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	instant

- Definition

Exercise price per share or per unit of warrants or rights outstanding.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 3
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481112/505-10-50-3

+ Details

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Data Type:	dtr-types:perShareItemType
Balance Type:	na
Period Type:	instant

- Definition

Number of securities into which the class of warrant or right may be converted. For example, but not limited to, 500,000 warrants may be converted into 1,000,000 shares.

+ References

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

The cash inflow from issuance of rights to purchase common shares at predetermined price (usually issued together with corporate debt).

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Name Accounting Standards Codification
-Section 45
-Paragraph 14
-Subparagraph (a)
-SubTopic 10
-Topic 230
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482740/230-10-45-14

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration

- Definition

The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

+ References

No definition available.

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Definition

Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

+ References

No definition available.

+ Details

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Data Type:	dtr-types:perShareItemType
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Period Type:	instant

- Definition

Detail information of subsequent event by type. User is expected to use existing line items from elsewhere in the taxonomy as the primary line items for this disclosure, which is further associated with dimension and member elements pertaining to a subsequent event.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 830
-SubTopic 30
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147481674/830-30-50-2

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Topic 855
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147483399/855-10-50-2

+ Details

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Data Type:	xbrli:stringItemType
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Period Type:	duration

- Definition

Period between issuance and expiration of outstanding warrant and right embodying unconditional obligation requiring redemption by transferring asset at specified or determinable date or upon event certain to occur, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)(i)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 2: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(2)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

Reference 3: http://www.xbrl.org/2009/role/commonPracticeRef
-Topic 820
-SubTopic 10
-Name Accounting Standards Codification
-Section 50
-Paragraph 2
-Subparagraph (bbb)(1)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147482106/820-10-50-2

+ Details

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:durationItemType
Balance Type:	na
Period Type:	instant

- Details

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Namespace Prefix:
Data Type:	na
Balance Type:
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- Details

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- Details

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- Details

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- Details

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Namespace Prefix:
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- Details

Name:	us-gaap_ClassOfWarrantOrRightAxis=cmps_PrefundedWarrantsMember
Namespace Prefix:
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Subsequent Events (Details) $ / shares in Units, $ in Millions			1 Months Ended
	Aug. 18, 2023	Oct. 08, 2021 USD ($)	Jan. 31, 2025 USD ($) day $ / shares shares	Feb. 27, 2025 USD ($)	Jan. 31, 2025 £ / shares shares
Subsequent Event [Line Items]
Ordinary share conversion ratio	1	1
Initial Public Offering \| American Depositary Shares
Subsequent Event [Line Items]
Amount of stock authorized		$ 150.0
Subsequent event \| Underwritten Offering
Subsequent Event [Line Items]
Issuance of warrants			$ 150.0
Subsequent event \| Initial Public Offering \| American Depositary Shares
Subsequent Event [Line Items]
Amount of stock authorized				$ 150.0
2025 ADS Warrants \| Subsequent event \| Underwritten Offering
Subsequent Event [Line Items]
Sale of stock, shares issued in transaction (in shares) \| shares			24,014,728
Ordinary share conversion ratio			1
Sale of stock, price per share (in dollars per share) \| (per share)			$ 4.2750		£ 0.008
Purchase of warrants (in shares) \| shares			24,014,728		24,014,728
Proceeds from warrant exercises, fully exercised			$ 353.0
Purchase price (in dollars per share) \| $ / shares			$ 5.7960
Term of warrants and rights outstanding			3 years		3 years
Threshold consecutive trading days \| day			3
Prefunded Warrants \| Subsequent event \| Underwritten Offering
Subsequent Event [Line Items]
Sale of stock, price per share (in dollars per share) \| $ / shares			$ 4.2649
Purchase of warrants (in shares) \| shares			11,044,720		11,044,720
Purchase price (in dollars per share) \| $ / shares			$ 0.0001