Common Stock and Warrants - Additional Information (Detail) $ / shares in Units, $ in Thousands			6 Months Ended
	Jun. 16, 2021 USD ($) Vote $ / shares shares	Feb. 04, 2021 shares	Sep. 30, 2021 USD ($) $ / shares shares	Sep. 30, 2020 USD ($)	Mar. 31, 2021 $ / shares shares
Class Of Stock [Line Items]
Stock split description	Each share of Class B common stock is convertible into one share of Class A common stock any time at the option of the holder and is automatically converted into one share of Class A common stock upon transfer		The shares and net loss per common share prior to the Merger have been retroactively restated as shares reflecting the exchange ratio established in the Merger (each outstanding share of 23andMe, Inc. Class A common stock was exchanged for 2.293698169 shares of the Company’s Class A common stock, and each outstanding share of 23andMe, Inc. Class B common stock, including all shares of 23andMe, Inc. preferred stock (which were converted to shares of 23andMe, Inc. Class B common stock immediately prior to the Merger), was exchanged for 2.293698169 shares of the Company’s Class B common stock).
Common stock, shares authorized	1,490,000,000
Preferred stock, shares authorized	10,000,000
Preferred stock, par value | $ / shares	$ 0.0001
Preferred stock, shares issued			0
Preferred stock, shares outstanding			0
Proceeds from issuance of common stock | $			$ 309,720
Warrants exercised			0
Public Warrants
Class Of Stock [Line Items]
Expiration			5 years
Class A Common Stock [Member]
Class Of Stock [Line Items]
Common Stock, Par value | $ / shares	$ 0.0001		$ 0.0001		$ 0.0001
Exchange Ratio	2.293698169		2.293698169
Common stock, shares authorized	1,140,000,000		1,140,000,000
Number of votes | Vote	1
Common Stock, Shares, Issued			93,409,227		20,713,076
Common Stock, Shares, Outstanding			93,409,227		20,713,076
Number of Warrants			25,065,608
Trading days		20 days
Share Redemption Trigger Price | $ / shares			$ 18.00
Class A Common Stock [Member] | The Anne Wojcicki Foundation [Member]
Class Of Stock [Line Items]
Common stock shares subscribed	2,500,000
Class A Common Stock [Member] | Private Placement Warrants
Class Of Stock [Line Items]
Number of Warrants			8,113,999
Exercise price | $ / shares			$ 11.50
Number of Days after the completion of an initial business combination			30 days
Class of Warrant or Right Redemption Threshold Trading Days			10 days
Class of warrants or rights redemption price per warrant | $ / shares			$ 10.00
Class A Common Stock [Member] | Public Warrants
Class Of Stock [Line Items]
Number of Warrants			16,951,609
Exercise price | $ / shares			$ 11.50
Class A Common Stock [Member] | 23andMe, Inc [Member]
Class Of Stock [Line Items]
Common Stock, Par value | $ / shares	$ 0.00001
Class A Common Stock [Member] | VG Acquisition Sponsor LLC [Member]
Class Of Stock [Line Items]
Expiry date			5 years
Trading days		20 days
Class A Common Stock [Member] | VG Acquisition Sponsor LLC [Member] | Private Placement Warrants
Class Of Stock [Line Items]
Number of Warrants			8,113,999
Exercise price | $ / shares			$ 11.50
Class A Common Stock [Member] | VG Acquisition Sponsor LLC [Member] | Public Warrants
Class Of Stock [Line Items]
Number of Warrants			16,951,609
Exercise price | $ / shares			$ 11.50
Class A Common Stock [Member] | PIPE
Class Of Stock [Line Items]
Common Stock, Par value | $ / shares	$ 10.00
Common stock shares subscribed	25,000,000
Proceeds from issuance of common stock | $	$ 250,000
Class B Common Stock [Member]
Class Of Stock [Line Items]
Common Stock, Par value | $ / shares	$ 0.0001		$ 0.0001		$ 0.0001
Exchange Ratio	2.293698169		2.293698169
Common stock, shares authorized	350,000,000		350,000,000
Number of votes | Vote	10
Common Stock, Shares, Issued			313,759,355		103,816,708
Common Stock, Shares, Outstanding			313,759,355		103,816,708
Class B Common Stock [Member] | 23andMe, Inc [Member]
Class Of Stock [Line Items]
Common Stock, Par value | $ / shares	$ 0.00001
Class B Common Stock [Member] | VG Acquisition Sponsor LLC [Member]
Class Of Stock [Line Items]
Common Stock, Shares, Outstanding		3,814,125
Common Class C [Member]
Class Of Stock [Line Items]
Common Stock, Shares, Outstanding			0
Share Price Less Than Dollar Eighteen And Greater Than Or Equals To Ten Point Zero Zero | Class A Common Stock [Member] | Public Warrants
Class Of Stock [Line Items]
Exercise price | $ / shares			$ 0.10
Share Redemption Trigger Price | $ / shares			$ 10.00
Class of warrants redemption notice period			30 days
Share Price Less Than Dollar Eighteen And Greater Than Or Equals To Ten Point Zero Zero | Minimum [Member] | Class A Common Stock [Member] | Public Warrants
Class Of Stock [Line Items]
Exercise price | $ / shares			$ 18.00
Share Price Equals Or Exceeds Dollar Eighteen | Class A Common Stock [Member] | Public Warrants
Class Of Stock [Line Items]
Exercise price | $ / shares			$ 0.01
Class of Warrant or Right Redemption Threshold Consecutive Trading Days			20 days
Class of Warrant or Right Redemption Threshold Trading Days			30 days
Share Redemption Trigger Price | $ / shares			$ 18.00
Class of warrants redemption notice period			30 days