Investment Securities (Fair Value of Securities Pledged and Accepted as Collateral) (Details) - USD ($) $ in Millions |
Mar. 31, 2023 |
Dec. 31, 2022 |
---|---|---|
Summary of Investment Holdings [Line Items] | ||
Permitted by contract or custom to sell or repledge | $ 1,357 | $ 1,266 |
Permitted amount repledged to others | 1,357 | 1,266 |
Asset Pledged as Collateral | ||
Summary of Investment Holdings [Line Items] | ||
Debt securities, pledged to others | $ 27,586 | $ 24,708 |