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Revenue and Interest Recognized in Income (Details) - Life policy reserves: - USD ($) $ in Millions | 3 Months Ended | 9 Months Ended
--- | --- | ---
Sep. 30, 2025 | Sep. 30, 2024 | Sep. 30, 2025 | Sep. 30, 2024
Liability for Future Policy Benefit, Activity [Line Items] |  |  |  |
Gross premiums | $ 90 | $ 87 | $ 268 | $ 262
Interest accretion | 19 | 18 | 57 | 55
Term Life Insurance |  |  |  |
Liability for Future Policy Benefit, Activity [Line Items] |  |  |  |
Gross premiums | 76 | 72 | 227 | 221
Interest accretion | 13 | 12 | 39 | 38
Whole Life Insurance |  |  |  |
Liability for Future Policy Benefit, Activity [Line Items] |  |  |  |
Gross premiums | 14 | 15 | 41 | 41
Interest accretion | $ 6 | $ 6 | $ 18 | $ 17

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