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Income Taxes (Significant components of the Company's deferred tax assets and liabilities) (Details) - USD ($) $ in Millions | Dec. 31, 2024 | Dec. 31, 2023
--- | --- | ---
Deferred Tax Assets: |  |
Property and casualty claim and claim adjustment expense reserves | $ 234 | $ 202
Unearned premium reserves | 225 | 213
Policyholder reserves | 0 | 160
Deferred revenue | 59 | 62
Employee benefits | 13 | 23
Deferred retroactive reinsurance benefit | 89 | 88
Net unrealized losses | 494 | 418
Other assets | 107 | 111
Gross deferred tax assets | 1,221 | 1,277
Deferred Tax Liabilities: |  |
Investment valuation differences | 130 | 83
Deferred acquisition costs | 140 | 126
Policyholder reserves | 48 | 0
Software and hardware | 17 | 18
Other liabilities | 36 | 34
Gross deferred tax liabilities | 371 | 261
Net deferred tax asset | $ 850 | $ 1,016

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