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Derivatives - Schedule of Interest Rate Hedging Instruments (Details) - Short position - USD ($) $ in Thousands | Mar. 31, 2025 | Dec. 31, 2024
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Interest rate swaps | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | $ (6,335,000) | $ (5,385,000)
Derivative, Average Fixed Interest Rate | 3.68% | 3.61%
Interest rate swaps | Not Designated as Hedging Instrument, Economic Hedge | Less than 5 years |  |
Derivative [Line Items] |  |
Notional balance | $ (1,275,000) | $ (1,275,000)
Derivative, Average Fixed Interest Rate | 3.42% | 3.42%
Interest rate swaps | Not Designated as Hedging Instrument, Economic Hedge | Less than 7 years |  |
Derivative [Line Items] |  |
Notional balance | $ (3,510,000) | $ (3,085,000)
Derivative, Average Fixed Interest Rate | 3.66% | 3.61%
Interest rate swaps | Not Designated as Hedging Instrument, Economic Hedge | 9-10 years |  |
Derivative [Line Items] |  |
Notional balance | $ (1,350,000) | $ (1,025,000)
Derivative, Average Fixed Interest Rate | 3.92% | 3.83%
Interest rate swaps | Not Designated as Hedging Instrument, Economic Hedge | 10-15 years |  |
Derivative [Line Items] |  |
Notional balance | $ (200,000) |
Derivative, Average Fixed Interest Rate | 3.93% |
U.S. Treasury futures | 30-year | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | $ (766,500) | $ (516,500)
U.S. Treasury futures | 10-year | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | (795,000) | (735,000)
U.S. Treasury futures | Not Designated as Hedging Instrument, Economic Hedge |  |
Derivative [Line Items] |  |
Notional balance | $ (1,561,500) | $ (1,251,500)

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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 815 -SubTopic 40 -Name Accounting Standards Codification -Section 50 -Paragraph 5 -Subparagraph (f) -Publisher FASB -URI https://asc.fasb.org/1943274/2147480237/815-40-50-5 + Details
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