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Investment Securities (Narrative) (Details) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($)
Securities with no credit impairment in unrealized loss position | 1,289 |  |
Loan interest receivable | $ 49 | $ 36 |
Securities gains and losses | 0 | $ 0 |
Securities gains |  |  | $ 1
Securities losses |  |  | $ (1)
Carrying value of securities pledged | 3,200 |  |
Pledged to the FHLB as collateral for potential future borrowings - investment securities | 1,000 |  |
Collateral for potential future borrowings | 2,200 |  |
Liabilities secured by pledged collateral | $ 1,000 |  |
U.S. Treasury and other U.S. government agency securities |  |  |
Securities with no credit impairment in unrealized loss position | 27 |  |
Residential mortgage-backed securities |  |  |
Securities with no credit impairment in unrealized loss position | 1,008 |  |
Commercial Mortgage Backed Securities |  |  |
Securities with no credit impairment in unrealized loss position | 254 |  |

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