Business Combinations Line Items

No definition available.

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Data Type:	xbrli:stringItemType
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- Definition

Company's common share

+ References

No definition available.

+ Details

Name:	atai_CompanysCommonShare
Namespace Prefix:	atai_
Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Incremental Fair Value Of Atai Restricted Stock Units Issued For Consideration At Closing That Is Attributable To The Post Combination Entity

+ References

No definition available.

+ Details

Name:	atai_IncrementalFairValueOfAtaiRestrictedStockUnitsIssuedForConsiderationAtClosingThatIsAttributableToThePostCombinationEntity
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Settlement Of Accounts Payable

+ References

No definition available.

+ Details

Name:	atai_SettlementOfAccountsPayable
Namespace Prefix:	atai_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of warrants or rights outstanding.

+ References

No definition available.

+ Details

Name:	us-gaap_ClassOfWarrantOrRightOutstanding
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Data Type:	xbrli:sharesItemType
Balance Type:	na
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- Definition

Number of shares of other common stock instruments held by shareholder, including, but not limited to, exchangeable shares.

+ References

No definition available.

+ Details

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Data Type:	xbrli:sharesItemType
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- Definition

Total number of common shares of an entity that have been sold or granted to shareholders (includes common shares that were issued, repurchased and remain in the treasury). These shares represent capital invested by the firm's shareholders and owners, and may be all or only a portion of the number of shares authorized. Shares issued include shares outstanding and shares held in the treasury.

+ References

+ Details

Name:	us-gaap_CommonStockSharesIssued
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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	instant

- Definition

Amount of accrued but unpaid interest on deposit liabilities.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 942
-SubTopic 210
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(15)(5))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147478546/942-210-S99-1

+ Details

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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant

- Definition

Number of shares of stock issued during the period pursuant to acquisitions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(28))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 210
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(29))
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480566/210-10-S99-1

Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef
-Topic 505
-SubTopic 10
-Name Accounting Standards Codification
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480008/505-10-S99-1

+ Details

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Data Type:	xbrli:sharesItemType
Balance Type:	na
Period Type:	duration

- Details

Name:	srt_ScheduleOfEquityMethodInvestmentEquityMethodInvesteeNameAxis=atai_BeckleyPsytechLimitedMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_StatementClassOfStockAxis=atai_SeriesCSharesMember
Namespace Prefix:
Data Type:	na
Balance Type:
Period Type:

- Details

Name:	us-gaap_StatementClassOfStockAxis=atai_SeriesCWarrantsMember
Namespace Prefix:
Data Type:	na
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- Details

Name:	us-gaap_AwardTypeAxis=us-gaap_RestrictedStockUnitsRSUMember
Namespace Prefix:
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Acquisitions - Schedule of Fair Values of Consideration Paid (Parenthetical) (Details) - USD ($) $ in Thousands		12 Months Ended
	Nov. 05, 2025	Dec. 31, 2025	Oct. 31, 2025	Dec. 31, 2024
Business Combinations [Line Items]
Common Stock, Shares, Issued		363,280,522		167,959,752
Stock options issued as replacement awards		1,546,258
Beckley Psytech Limited [Member]
Business Combinations [Line Items]
Common Stock, Shares, Issued			900,901
Company's common share		4.48
Accrued interest		$ 10,300
Settlement of accounts payable		$ 200
Stock options issued as replacement awards	6,971,912
Beckley Psytech Limited [Member] \| Series C Shares [Member]
Business Combinations [Line Items]
Company's outstanding		45,500,000
Beckley Psytech Limited [Member] \| Series C Warrants [Member]
Business Combinations [Line Items]
Purchase of warrant		8,500,000
Restricted Stock Units (RSUs) [Member]
Business Combinations [Line Items]
Common Stock, Shares, Issued		93,580,831
Incremental fair value of atai restricted stock units issued for consideration at closing that is attributable to the post-combination entity		$ 6,971,912
Restricted Stock Units (RSUs) [Member] \| Beckley Psytech Limited [Member]
Business Combinations [Line Items]
Common Stock, Shares, Issued		6,971,912
Stock options issued as replacement awards	8,695,937