Derivative Instruments and Hedging Activities - Futures (Details) - Futures, net - USD ($) |
3 Months Ended | 12 Months Ended |
|---|---|---|
Mar. 31, 2026 |
Dec. 31, 2025 |
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| Derivative [Line Items] | ||
| Notional | $ (6,354,300,000) | $ (4,357,800,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 2 years 3 months 14 days | 2 years 11 months 30 days |
| U.S. Treasury Futures | 2 Years | ||
| Derivative [Line Items] | ||
| Notional | $ (2,312,800,000) | $ (1,448,000,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 2 months 30 days | 2 months 29 days |
| U.S. Treasury Futures | 5 Year | ||
| Derivative [Line Items] | ||
| Notional | $ (1,701,200,000) | $ (1,047,400,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 2 months 30 days | 2 months 29 days |
| U.S. Treasury Futures | 10 Year | ||
| Derivative [Line Items] | ||
| Notional | $ (501,100,000) | $ (115,700,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 2 months 18 days | 2 months 18 days |
| U.S. Treasury Futures | 20 Year | ||
| Derivative [Line Items] | ||
| Notional | $ (190,800,000) | $ (283,300,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 2 months 18 days | 2 months 18 days |
| Eris SOFR Swap Futures | 5 Year | ||
| Derivative [Line Items] | ||
| Notional | $ (1,200,000,000) | $ (1,200,000,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 5 years 2 months 18 days | 5 years 2 months 17 days |
| Eris SOFR Swap Futures | 10 Year | ||
| Derivative [Line Items] | ||
| Notional | $ (830,000,000) | $ (830,000,000) |
| Carrying Value | $ 0 | $ 0 |
| Weighted Average Months to Expiration | 10 years 2 months 20 days | 10 years 2 months 19 days |
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- Definition Average remaining period until maturity of the derivative contract, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days. No definition available.
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- Definition Fair value of the assets less the liabilities of a derivative or group of derivatives. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Nominal or face amount used to calculate payment on derivative. Reference 1: http://www.xbrl.org/2003/role/exampleRef
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