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Investments (Narrative) (Details) |  |  | 12 Months Ended
--- | --- | --- | ---
Oct. 01, 2021 USD ($) | Nov. 01, 2020 USD ($) | Dec. 31, 2021 USD ($) investment shares | Dec. 31, 2020 USD ($) | Dec. 31, 2019 USD ($)
Schedule of Investments [Line Items] |  |  |  |  |
Investment securities available for sale transferred to held to maturity fair value, net of tax | $ (12,700,000) | $ 5,900,000 | $ (12,659,000) | $ 5,894,000 | $ 72,512,000
Reclassification of unrealized losses, net of tax | 9,700,000 | 4,500,000 | (10,883,000) | 4,157,000 | $ 71,149,000
Interest receivable, available-for-sale debt securities |  |  | 22,300,000 | 17,600,000 |
Interest receivable, held-to-maturity debt securities |  |  | 6,600,000 | 5,400,000 |
Debt securities, accrued interest, writeOff |  |  | $ 0 | 0 |
Number of investments in continuous unrealized loss position for more than twelve months | investment |  |  | 37 |  |
Unrealized losses related to marketability of securities or issuers ability to honor redemption obligations |  |  | $ 0 |  |
Investment value deemed to be OTTI |  |  | 0 |  |
Investment securities, aggregate carrying value, pledged as collateral |  |  | 5,740,000,000 | $ 4,640,000,000 |
Debt securities, held-to-maturity, nonaccrual |  |  | $ 0 |  |
Visa Class B Common Stock |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investment owned (in shares) | shares |  |  | 353,577 |  |
Total past due |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Debt securities |  |  | $ 0 |  |
Mortgage Backed Securities |  |  |  |  |
Schedule of Investments [Line Items] |  |  |  |  |
Investment securities available for sale transferred to held to maturity amortized cost | 451,700,000 | 1,460,000,000 |  |  |
Investment securities available for sale transferred to held to maturity fair value | $ 439,000,000 | $ 1,470,000,000 |  |  |
Weighted average contractual maturity (years) |  | 18 years |  |  |

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