Convertible Promissory Notes - Additional Information (Detail) € / shares in Units, $ / shares in Units, € in Thousands					3 Months Ended		6 Months Ended		12 Months Ended
	May 31, 2022 USD ($)	May 31, 2022 EUR (€) € / shares	Jun. 10, 2021 USD ($) shares	Dec. 31, 2020 USD ($)	Jun. 30, 2022 USD ($) $ / shares shares	Jun. 30, 2021 USD ($)	Jun. 30, 2022 USD ($) $ / shares	Jun. 30, 2021 USD ($)	Dec. 31, 2021 USD ($)	Dec. 31, 2021 EUR (€) € / shares	Jun. 30, 2022 EUR (€)	Feb. 28, 2022	Jun. 30, 2021 € / shares	Jun. 30, 2021 USD ($) $ / shares	May 31, 2021 USD ($)	Jan. 01, 2021 USD ($)	Dec. 01, 2020 USD ($)	Oct. 31, 2020 USD ($) $ / shares	Oct. 31, 2020 EUR (€)	Mar. 16, 2020 USD ($)	Nov. 30, 2018 USD ($)	Nov. 30, 2018 EUR (€)	Oct. 31, 2018 USD ($)	Oct. 31, 2018 EUR (€)
Debt Instrument [Line Items]
Debt conversion price | (per share)													€ 1,350	$ 1,654
Interest expense						$ 100,000		$ 200,000
Amortization of debt discount							$ 0	191,000
Unamortized debt discount														$ 93,000
Fair value amount of convertible promissory note					$ 28,800,000		28,800,000
General and administrative expense					$ 17,221,000	$ 37,331,000	35,203,000	$ 46,604,000
Second Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued															$ 5,000,000.0
Common Stock [Member]
Debt Instrument [Line Items]
Stock issued during period, convertible share | shares					960,000
ATAI LIFE SCIENCES N.V. [Member]
Debt Instrument [Line Items]
Debt conversion price | $ / shares																		$ 17.00
Face value of convertible notes | €																			€ 1
Perception March 2020 Notes [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued																				$ 3,900
Convertible promissory notes, interest rate																				5.00%
Fair value of ordinary shares			$ 600,000
Perception December 2020 Convertible Note Agreement [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued																	$ 12,000,000.0
Convertible promissory notes, interest rate												5.00%
Fair value of derivative liabilities				$ 400,000
Proceeds from licensing and collaboration arrangement			20,000,000.0
Gain from change in fair value of the derivative liability			41,000
Loss on extinguishment of notes			500,000
Debt carrying value			2,700,000
Fair value of ordinary shares			2,200,000
Gain (loss) from change in fair value of the derivative liability			$ 41,000
Perception December 2020 Convertible Note Agreement [Member] | Series A Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible notes conversion, shares issued | shares			6,456,595
Perception December 2020 Convertible Note Agreement [Member] | First Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued				$ 6,200,000												$ 800,000	$ 7,000,000.0
Perception December 2020 Convertible Note Agreement [Member] | Second Tranche Funding [Member]
Debt Instrument [Line Items]
Fair value of derivative liabilities					$ 300,000		300,000
Perception December 2020 Convertible Note Agreement [Member] | ATAI LIFE SCIENCES N.V. [Member] | Series A Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible notes conversion, shares issued | shares			5,403,791
Perception December 2020 Convertible Note Agreement [Member] | ATAI LIFE SCIENCES N.V. [Member] | Second Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued															4,200,000
Perception December 2020 Convertible Note Agreement [Member] | Sonia Weiss Pick And Family [Member] | Series A Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible notes conversion, shares issued | shares			440,415
Perception December 2020 Convertible Note Agreement [Member] | Sonia Weiss Pick And Family [Member] | Second Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued															300
Perception December 2020 Convertible Note Agreement [Member] | Other Investors [Member] | Series A Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible notes conversion, shares issued | shares			584,580
Perception December 2020 Convertible Note Agreement [Member] | Other Investors [Member] | Second Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued															400
Perception December 2020 Convertible Note Agreement [Member] | Apeiron [Member] | Series A Preferred Stock [Member]
Debt Instrument [Line Items]
Convertible notes conversion, shares issued | shares			27,809
Perception December 2020 Convertible Note Agreement [Member] | Apeiron [Member] | Second Tranche Funding [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued															$ 200,000
Perception December 2020 Convertible Note Agreement [Member] | Qualified Sale of Preferred Stock [Member]
Debt Instrument [Line Items]
Minimum proceeds expected from sale of preferred stock for debt conversion							$ 5,000,000.0
Debt conversion price, discount percentage							25.00%
Perception December 2020 Convertible Note Agreement [Member] | Licensing Transaction [Member]
Debt Instrument [Line Items]
Minimum licensing transaction for debt conversion							$ 5,000.0
Debt conversion price | $ / shares					$ 0.75		$ 0.75
Debt conversion price, threshold percentage				75.00%
Perception December 2020 Convertible Note Agreement [Member] | Change In control [Member]
Debt Instrument [Line Items]
Debt conversion price | $ / shares					$ 0.75		$ 0.75
Two Thousand Eighteen Convertible Note Agreement [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued					$ 100,000		$ 100,000				€ 100										$ 200,000	€ 200	$ 1,000,000.0	€ 800
Debt conversion price | € / shares		€ 17.00								€ 17.00
Fair value of ordinary shares	$ 1,100,000	€ 1,000							$ 6,900,000	€ 5,800
Aggregate principal amount				$ 1,200,000
Two Thousand Eighteen Convertible Note Agreement [Member] | Maximum [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued																					$ 1,200,000	€ 1,000
Two Thousand Eighteen Convertible Note Agreement [Member] | Apeiron [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued																		$ 600,000	500
Two Thousand Eighteen Convertible Note Agreement [Member] | Other Shareholder [Member]
Debt Instrument [Line Items]
Convertible promissory notes issued																		$ 400,000	€ 300