Deposits - Schedule of Deposits (Details) - USD ($) $ in Millions	Dec. 31, 2023	Dec. 31, 2022
Amount
Interest-bearing checking and money market accounts	$ 30,700	$ 22,511
Savings accounts	8,773	11,645
Certificates of deposit	21,554	12,510
Non-interest-bearing accounts	20,499	12,055
Total deposits	$ 81,526	$ 58,721
Percent of Total
Interest-bearing checking and money market accounts	37.66%	38.34%
Savings accounts	10.76%	19.83%
Certificates of deposit	26.44%	21.30%
Non-interest-bearing accounts	25.14%	20.53%
Total deposits	100.00%	100.00%
Weighted Average Interest Rate
Interest-bearing checking and money market accounts	3.51%	2.66%
Savings accounts	2.67%	1.30%
Certificates of deposit	4.42%	2.04%
Non-interest-bearing accounts	0.00%	0.00%
Total deposits	2.79%	1.71%