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Investment Securities - Narrative (Details) |  | 3 Months Ended |  |
--- | --- | --- | --- | ---
Mar. 13, 2023 USD ($) | Mar. 31, 2023 USD ($) Investments | Mar. 31, 2022 USD ($) | Dec. 31, 2022 USD ($) Investments | Dec. 31, 2021 USD ($)
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |
Debt Securities, Held-to-Maturity, Amortized Cost, after Allowance for Credit Loss, Transfer, Amount | $ 23,000,000 |  |  |  |
Debt Securities, Held-To-Maturity, After Allowance For Credit Loss, Transfer, Amount | 13,200,000 |  |  |  |
Allowance for Credit Losses | $ 800,000 |  |  | $ 0 |
Debt Securities, Held-to-maturity, Allowance for Credit Loss |  | $ 700,000 | $ 1,600,000 | 1,900,000 | $ 0
Interest Receivable |  | 113,700,000 |  | 118,300,000 |
Debt Securities, Available-for-sale, Realized Gain |  | 0 | 0 |  |
Debt Securities, Available-for-sale, Realized Loss |  | (23,400,000) | $ 0 |  |
Securities Sold under Agreements to Repurchase, Fair Value of Collateral |  | 3,607,300,000 |  | 4,998,900,000 |
Securities Loaned or Sold under Agreements to Repurchase, Fair Value Disclosure |  | $ 3,228,500,000 |  | $ 4,432,000,000 |
Investment securities in an unrealized loss position (securities) | Investments |  | 1,023 |  | 1,222 |
Callable Within One Year |  |  |  |  |
Schedule of Held-to-maturity Securities [Line Items] |  |  |  |  |
Amortized cost of investment securities callable after one year but within five years |  | $ 1,525,900,000 |  |  |
Fair value of investment securities callable after one year but within five years |  | 1,446,900,000 |  |  |
Callable structured notes amortized costs |  | $ 0 |  |  |

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