Borrowings - Detailed Information on FHLB Advances and Other Borrowings (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2022	Jun. 30, 2021	Jun. 30, 2022	Jun. 30, 2021
Debt Disclosure [Abstract]
Maximum outstanding at any month end	$ 4,001	$ 3,575	$ 4,001	$ 4,737
Average outstanding balance	2,107	3,622	2,013	3,800
Average remaining borrowing capacity	$ 3,261	$ 5,295	$ 3,851	$ 5,389
Weighted average interest rate	1.09%	0.45%	0.91%	0.44%