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Other Assets - Derivative Instruments (Details) - USD ($) $ in Thousands | Sep. 30, 2025 | Dec. 31, 2024
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Swap |  |
Derivative [Line Items] |  |
Notional Amount | $ 3,773,600 | $ 3,313,750
Weighted Average Fixed-Pay Interest Rate | 2.63% | 2.20%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Swap | Within 30 days |  |
Derivative [Line Items] |  |
Notional Amount | $ 0 | $ 450,000
Weighted Average Fixed-Pay Interest Rate | 0.00% | 1.16%
Weighted Average Variable Interest Rate | 0.00% | 4.49%
Swap | Over 30 days to 3 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 0 | $ 100,000
Weighted Average Fixed-Pay Interest Rate | 0.00% | 1.65%
Weighted Average Variable Interest Rate | 0.00% | 4.49%
Swap | Over 3 months to 6 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 0 | $ 125,000
Weighted Average Fixed-Pay Interest Rate | 0.00% | 2.69%
Weighted Average Variable Interest Rate | 0.00% | 4.49%
Swap | Over 6 months to 12 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 0 | $ 0
Weighted Average Fixed-Pay Interest Rate | 0.00% | 0.00%
Weighted Average Variable Interest Rate | 0.00% | 0.00%
Swap | Over 12 months to 24 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 1,591,500 | $ 450,000
Weighted Average Fixed-Pay Interest Rate | 1.74% | 1.12%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Swap | Over 24 months to 36 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 361,500 | $ 1,045,000
Weighted Average Fixed-Pay Interest Rate | 3.33% | 1.84%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Swap | Over 36 months to 48 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 332,800 | $ 24,600
Weighted Average Fixed-Pay Interest Rate | 2.96% | 4.28%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Swap | Over 48 months to 60 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 793,700 | $ 574,000
Weighted Average Fixed-Pay Interest Rate | 3.37% | 3.28%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Swap | Over 60 months to 72 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 0 | $ 0
Weighted Average Fixed-Pay Interest Rate | 0.00% | 0.00%
Weighted Average Variable Interest Rate | 0.00% | 0.00%
Swap | Over 72 months |  |
Derivative [Line Items] |  |
Notional Amount | $ 694,100 | $ 545,150
Weighted Average Fixed-Pay Interest Rate | 3.31% | 3.42%
Weighted Average Variable Interest Rate | 4.24% | 4.49%
Interest Rate Swap |  |
Derivative [Line Items] |  |
Notional Amount | $ 2,100,000 |
ERIS Swap Futures |  |
Derivative [Line Items] |  |
Notional Amount | $ 1,700,000 |

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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/2009/role/commonPracticeRef -Topic 815 -SubTopic 20 -Name Accounting Standards Codification -Section 25 -Paragraph 6A -Publisher FASB -URI https://asc.fasb.org/1943274/2147480682/815-20-25-6A Reference 2: 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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