Basis of Reporting and Accounting - Reporting and Accounting Policies - Allowance for Credit Loss (Details) - USD ($) $ in Millions |
3 Months Ended | 9 Months Ended | ||
|---|---|---|---|---|
Sep. 30, 2026 |
Sep. 30, 2025 |
Sep. 30, 2026 |
Sep. 30, 2025 |
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| Premium Receivable, Allowance for Credit Loss [Roll Forward] | ||||
| Allowance for credit losses, beginning of period | $ 544 | $ 501 | $ 552 | $ 460 |
| Increase in allowance | 228 | 211 | 641 | 540 |
| Write-offs | (184) | (196) | (605) | (484) |
| Allowance for credit losses, end of period | $ 588 | $ 516 | $ 588 | $ 516 |
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- Definition The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross premiums receivable to net realizable value. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition Amount of increase (decrease) in allowance for credit loss on premium receivable. Reference 1: http://fasb.org/us-gaap/role/ref/otherTransitionRef
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- Definition A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period. No definition available.
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- Definition Amount of writeoff of premium receivable, charged against allowance for credit loss. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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