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Claim and Claim Adjustment Expense Reserves and Future Policy Benefit Reserves (Reconciliation of claim and claim adjustment expense reserves) (Details) - USD ($) $ in Millions | 9 Months Ended
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Sep. 30, 2022 | Sep. 30, 2021
Reserves, beginning of year: |  |
Gross | $ 24,174 | $ 22,706
Ceded | 4,969 | 4,005
Net reserves, beginning of year | 19,205 | 18,701
Reduction of net reserves due to Excess Workers' Compensation Loss Portfolio Transfer | 0 | (632)
Net incurred claim and claim adjustment expenses: |  |
Provision for insured events of current year | 4,638 | 4,474
Increase (decrease) in provision for insured events of prior years | (144) | (130)
Amortization of discount | 131 | 137
Total net incurred | 4,625 | 4,481
Net payments attributable to: |  |
Current year events | (523) | (629)
Prior year events | (3,371) | (2,874)
Total net payments | (3,894) | (3,503)
Foreign currency translation adjustment and other | (383) | (51)
Net reserves, end of period | 19,553 | 18,996
Ceded reserves, end of period | 5,147 | 4,836
Gross reserves, end of period | $ 24,700 | $ 23,832

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- Definition Amount, after effects of reinsurance, of payments to settle claims incurred in the current period and related claims settlement costs. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 944 -SubTopic 40 -Section 50 -Paragraph 3 -Subparagraph (c) -URI https://asc.fasb.org/extlink&oid=116884095&loc=d3e14764-158437 + Details
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