Condensed Consolidated Statements of Cash Flows (Parenthetical) $ in Millions	12 Months Ended
Dec. 31, 2020 USD ($)
Statement of Cash Flows [Abstract]
Proceeds from a related party convertible promissory note	$ 0.3

Proceeds from a related party convertible promissory note

No definition available.

Name:	atai_ProceedsFromARelatedPartyConvertiblePromissoryNote
Namespace Prefix:	atai_
Data Type:	xbrli:monetaryItemType
Balance Type:	debit
Period Type:	duration