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Investment Securities (Narrative) (Details) $ in Millions | 3 Months Ended |
--- | --- | ---
Jun. 30, 2022 USD ($) | Jun. 30, 2021 USD ($) | Dec. 31, 2021 USD ($)
Securities with no credit impairment in unrealized loss position |  | 1,211 |  |
Loan interest receivable |  | $ 49 |  | $ 36
Securities gains and losses |  | 0 | $ 0 |
Investment securities available-for-sale, Amortized Cost |  | 22,785 |  | 17,116
Investment securities available-for-sale |  | 20,829 |  | 16,986
Carrying value of securities pledged |  | 2,800 |  |
Pledged to the FHLB as collateral for potential future borrowings |  | 1,300 |  |
Collateral for potential future borrowings |  | 1,600 |  |
Liabilities secured by pledged collateral |  | $ 977 |  |
U.S. Treasury and other U.S. government agency securities |  |  |  |
Securities with no credit impairment in unrealized loss position |  | 28 |  |
Investment securities available-for-sale, Amortized Cost |  | $ 2,925 |  | 3,010
Investment securities available-for-sale |  | $ 2,802 |  | 2,993
Residential Mortgage Backed Securities |  |  |  |
Securities with no credit impairment in unrealized loss position |  | 944 |  |
Investment securities available-for-sale, Amortized Cost | [1] | $ 14,767 |  | 13,397
Investment securities available-for-sale | [1] | $ 13,165 |  | 13,288
Commercial Mortgage Backed Securities |  |  |  |
Securities with no credit impairment in unrealized loss position |  | 239 |  |
Investment securities available-for-sale, Amortized Cost | [1] | $ 5,093 |  | 709
Investment securities available-for-sale | [1] | $ 4,862 |  | $ 705
[1] | Issued and/or guaranteed by U.S. government agencies or U.S. government-sponsored enterprises.

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