CONDENSED CONSOLIDATED STATEMENTS OF OPERATIONS - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2024	Sep. 30, 2023	Sep. 30, 2024	Sep. 30, 2023
Revenues:
Net interest revenues	$ 274	$ 251	$ 813	$ 693
Total net revenues	637	467	1,937	1,394
Operating expenses:
Brokerage and transaction	39	39	114	114
Technology and development	205	202	610	608
Operations	50	41	140	119
Marketing	59	28	190	79
General and administrative	133	230	385	1,036
Total operating expenses	486	540	1,439	1,956
Other income (expense), net	2	(2)	8	0
Income (loss) before income taxes	153	(75)	506	(562)
Provision for income taxes	3	10	11	9
Net income (loss)	150	(85)	495	(571)
Net income (loss) attributable to common stockholders:
Basic	150	(85)	495	(571)
Diluted	$ 150	$ (85)	$ 495	$ (571)
Net income (loss) per share attributable to common stockholders:
Basic (in dollars per share)	$ 0.17	$ (0.09)	$ 0.56	$ (0.64)
Diluted (in dollars per share)	$ 0.17	$ (0.09)	$ 0.55	$ (0.64)
Weighted-average shares used to compute net income (loss) per share attributable to common stockholders:
Basic (in shares)	884,108,545	895,108,790	880,182,573	898,999,464
Diluted (in shares)	905,544,750	895,108,790	903,555,592	898,999,464
Transaction-based revenues
Revenues:
Transaction-based revenues and other revenues	$ 319	$ 185	$ 975	$ 585
Other revenues
Revenues:
Transaction-based revenues and other revenues	$ 44	$ 31	$ 149	$ 116