CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022	Sep. 30, 2023	Sep. 30, 2022
Revenues:
Net interest revenues	$ 251	$ 128	$ 693	$ 257
Total net revenues	467	361	1,394	978
Operating expenses:
Brokerage and transaction	39	33	114	94
Technology and development	202	185	608	698
Operations	41	65	119	242
Marketing	28	19	79	74
General and administrative	230	233	1,036	727
Total operating expenses	540	535	1,956	1,835
Other (income) expense, net	2	0	0	2
Loss before income taxes	(75)	(174)	(562)	(859)
Provision for income taxes	10	1	9	3
Net loss	(85)	(175)	(571)	(862)
Net loss attributable to common stockholders:
Basic	(85)	(175)	(571)	(862)
Diluted	$ (85)	$ (175)	$ (571)	$ (862)
Net loss per share attributable to common stockholders:
Basic (in dollars per share)	$ (0.09)	$ (0.20)	$ (0.64)	$ (0.99)
Diluted (in dollars per share)	$ (0.09)	$ (0.20)	$ (0.64)	$ (0.99)
Weighted-average shares used to compute net loss per share attributable to common stockholders:
Basic (in shares)	895,108,790	882,356,575	898,999,464	875,055,571
Diluted (in shares)	895,108,790	882,356,575	898,999,464	875,055,571
Transaction-based revenues
Revenues:
Total transaction-based revenues	$ 185	$ 208	$ 585	$ 628
Other revenues
Revenues:
Total transaction-based revenues	$ 31	$ 25	$ 116	$ 93