Stockholders' Equity - Additional Information (Detail) $ / shares in Units, $ in Millions		6 Months Ended
	Dec. 08, 2023 $ / shares shares	Jun. 30, 2025 shares	Dec. 31, 2024 shares	Apr. 30, 2024 shares	Dec. 31, 2023 shares	Dec. 31, 2021 USD ($) $ / shares shares
Class of Stock [Line Items]
Preferred stock shares authorized		20,000,000
Allen and Company LLC [Member] | Warrants Convertible Into Class A Common Stock [Member]
Class of Stock [Line Items]
Class of warrants or rights number of securities covered by warrants or rights	150,000
Class of warrants or rights exercise price | $ / shares	$ 10
Common Class A [Member]
Class of Stock [Line Items]
Common stock shares authorized		1,000,000,000	1,000,000,000	204,590,500	200,228,024
Common Class A [Member] | Exercise of Warrants [Member]
Class of Stock [Line Items]
Stock issued during period shares new issues	109,459
Common Class A [Member] | Master Services Agreement With Astra Zeneca As Amended [Member]
Class of Stock [Line Items]
Class of warrants value of shares covered by warrants or rights | $						$ 100
Class of warrants or rights number of securities covered by warrants or rights						2,702,703
Class of warrants or rights exercise price | $ / shares						$ 37
Common Class B [Member]
Class of Stock [Line Items]
Common stock shares authorized		5,500,000	5,500,000		5,374,899
Stockholders equity stock split		1
Duration before which shares may be converted from one class to another		20 years
Share holding below which trigger is caused for conversion of stock from one class to another		10,000,000
Common Class B [Member] | Maximum [Member]
Class of Stock [Line Items]
Number of days for determining conversion of stock from class to another		150 days
Number of days for determining ownership of the founder below which conversion of stock from one class to another is triggered		150 days
Common Class B [Member] | Minimum [Member]
Class of Stock [Line Items]
Number of days for determining conversion of stock from class to another		90 days
Number of days for determining ownership of the founder below which conversion of stock from one class to another is triggered		90 days
Non-voting Common Stock [Member]
Class of Stock [Line Items]
Common stock shares authorized		0	0		66,946,627