CONDENSED CONSOLIDATED STATEMENTS OF REDEEMABLE CONVERTIBLE PREFERRED STOCK AND STOCKHOLDERS’ EQUITY - USD ($) $ in Thousands	Total	Series A Derivative Liability	Common Stock	Additional Paid-In Capital	Treasury Stock	Accumulated Other Comprehensive Income (Loss)	Accumulated Deficit
Beginning balance (in shares) at Dec. 31, 2023	0
Beginning balance at Dec. 31, 2023	$ 0
Increase (Decrease) in Temporary Equity [Roll Forward]
Issuance of Series A redeemable convertible preferred stock, net of derivative liability and issuance costs (in shares)		100,000
Issuance of Series A redeemable convertible preferred stock, net of derivative liability and issuance costs (related party)		$ 500,549
Accretion of redeemable convertible preferred stock (related party)	$ 150,762
Ending balance (in shares) at Jun. 30, 2024	100,000
Ending balance at Jun. 30, 2024	$ 651,311
Beginning balance (in shares) at Dec. 31, 2023			2,299,253,664
Beginning balance at Dec. 31, 2023	4,851,692		$ 230	$ 15,066,080	$ (20,716)	$ 4,850	$ (10,198,752)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(1,324,249)						(1,324,249)
Other comprehensive income	(9,009)					(9,009)
Tax withholding payments for net settlement of employee awards	(5,312)			(5,312)
Issuance of common stock upon vesting of employee RSUs (in shares)			12,732,126
Issuance of common stock upon vesting of employee RSUs	0		$ 2	(2)
Issuance of common stock under employee stock purchase plan (in shares)			4,601,557
Issuance of common stock under employee stock purchase plan	11,104			11,104
Issuance of common stock upon exercise of stock options (in shares)			2,098,557
Issuance of common stock upon exercise of stock options	2,311			2,311
Accretion of redeemable convertible preferred stock (related party)	(150,762)			(150,762)
Stock-based compensation	140,122			140,122
Ending balance (in shares) at Jun. 30, 2024			2,318,685,904
Ending balance at Jun. 30, 2024	$ 3,515,897		$ 232	15,063,541	(20,716)	(4,159)	(11,523,001)
Beginning balance (in shares) at Mar. 31, 2024	100,000
Beginning balance at Mar. 31, 2024	$ 504,450
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock (related party)	$ 146,861
Ending balance (in shares) at Jun. 30, 2024	100,000
Ending balance at Jun. 30, 2024	$ 651,311
Beginning balance (in shares) at Mar. 31, 2024			2,306,928,813
Beginning balance at Mar. 31, 2024	4,232,190		$ 231	15,134,686	(20,716)	(2,400)	(10,879,611)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(643,390)						(643,390)
Other comprehensive income	(1,759)					(1,759)
Tax withholding payments for net settlement of employee awards	(2,070)			(2,070)
Issuance of common stock upon vesting of employee RSUs (in shares)			6,472,275
Issuance of common stock upon vesting of employee RSUs	0		$ 1	(1)
Issuance of common stock under employee stock purchase plan (in shares)			4,601,557
Issuance of common stock under employee stock purchase plan	11,104			11,104
Issuance of common stock upon exercise of stock options (in shares)			683,259
Issuance of common stock upon exercise of stock options	786			786
Accretion of redeemable convertible preferred stock (related party)	(146,861)			(146,861)
Stock-based compensation	65,897			65,897
Ending balance (in shares) at Jun. 30, 2024			2,318,685,904
Ending balance at Jun. 30, 2024	$ 3,515,897		$ 232	15,063,541	(20,716)	(4,159)	(11,523,001)
Beginning balance (in shares) at Dec. 31, 2024	175,000	100,000
Beginning balance at Dec. 31, 2024	$ 1,299,842	$ 730,025
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock (related party)	$ 564,748
Ending balance (in shares) at Jun. 30, 2025	175,000	100,000
Ending balance at Jun. 30, 2025	$ 1,864,590	$ 1,084,589
Beginning balance (in shares) at Dec. 31, 2024	3,031,361,899		3,031,361,899
Beginning balance at Dec. 31, 2024	$ 3,872,812		$ 303	16,808,018	(20,716)	(2,099)	(12,912,694)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(905,603)						(905,603)
Other comprehensive income	16,715					16,715
Tax withholding payments for net settlement of employee awards	(9,449)			(9,449)
Issuance of common stock upon vesting of employee RSUs (in shares)			31,732,762
Issuance of common stock upon vesting of employee RSUs	0		$ 3	(3)
Issuance of common stock under employee stock purchase plan (in shares)			6,854,017
Issuance of common stock under employee stock purchase plan	$ 12,696		$ 1	12,695
Issuance of common stock upon exercise of stock options (in shares)	4,490,688		2,396,916
Issuance of common stock upon exercise of stock options	$ 1,274			1,274
Purchase of capped call options	(118,250)			(118,250)
Accretion of redeemable convertible preferred stock (related party)	(564,748)			(564,748)
Stock-based compensation	$ 102,144			102,144
Ending balance (in shares) at Jun. 30, 2025	3,072,345,594		3,072,345,594
Ending balance at Jun. 30, 2025	$ 2,407,591		$ 307	16,231,681	(20,716)	14,616	(13,818,297)
Beginning balance (in shares) at Mar. 31, 2025	175,000
Beginning balance at Mar. 31, 2025	$ 1,664,767
Increase (Decrease) in Temporary Equity [Roll Forward]
Accretion of redeemable convertible preferred stock (related party)	$ 199,823
Ending balance (in shares) at Jun. 30, 2025	175,000	100,000
Ending balance at Jun. 30, 2025	$ 1,864,590	$ 1,084,589
Beginning balance (in shares) at Mar. 31, 2025			3,048,800,731
Beginning balance at Mar. 31, 2025	3,183,675		$ 305	16,477,601	(20,716)	5,350	(13,278,865)
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Net loss	(539,432)						(539,432)
Other comprehensive income	9,266					9,266
Tax withholding payments for net settlement of employee awards	(6,172)			(6,172)
Issuance of common stock upon vesting of employee RSUs (in shares)			14,642,058
Issuance of common stock upon vesting of employee RSUs	0		$ 1	(1)
Issuance of common stock under employee stock purchase plan (in shares)			6,854,017
Issuance of common stock under employee stock purchase plan	12,696		$ 1	12,695
Issuance of common stock upon exercise of stock options (in shares)			2,048,788
Issuance of common stock upon exercise of stock options	861			861
Purchase of capped call options	(118,250)			(118,250)
Accretion of redeemable convertible preferred stock (related party)	(199,823)			(199,823)
Stock-based compensation	$ 64,770			64,770
Ending balance (in shares) at Jun. 30, 2025	3,072,345,594		3,072,345,594
Ending balance at Jun. 30, 2025	$ 2,407,591		$ 307	$ 16,231,681	$ (20,716)	$ 14,616	$ (13,818,297)