Deposit Liabilities (Schedule of Deposit Liabilities) (Details) - USD ($) $ in Millions	Dec. 31, 2020	Dec. 31, 2019
Deposits [Abstract]
Noninterest-bearing deposits	$ 128	$ 119
Interest-bearing Deposit Liabilities, by Component [Abstract]
Interest-bearing deposits, savings and money-market checking accounts	83,698	62,486
Total certificates of deposit	53,210	58,146
Interest-bearing deposits, other deposits	0	1
Total deposit liabilities	137,036	120,752
Certificates of deposit, $100,000 or more	25,800	25,600
Certificates of deposit, in excess of $250,000 federal insurance limits	$ 8,600	$ 8,200