Basis of Presentation and Significant Accounting Policies (Details) - USD ($) $ in Millions |
9 Months Ended | ||
|---|---|---|---|
Sep. 30, 2025 |
Sep. 30, 2026 |
Dec. 31, 2025 |
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| Accounting Policies [Abstract] | |||
| Cash and cash equivalents | $ 500 | $ 348 | |
| Securities lending transactions, initial collateral percentage value | 102.00% | ||
| Premium receivable, allowance for doubtful accounts | $ 180 | 167 | |
| Self-funded receivables, allowance for doubtful accounts | 236 | 145 | |
| Other receivables, allowance for doubtful accounts | $ 1,758 | $ 1,509 | |
| Allowance for credit loss, recovery from a customer | $ 237 | ||
| Release of allowance for doubtful accounts | (129) | ||
| Allowance for credit loss, recovery from customer for services rendered 2024 | 154 | ||
| Allowance for credit loss, recovery from a customer for services rendered in 2025 | $ 83 |
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- Definition Allowance for credit loss, recovery from a customer for services rendered in 2025 No definition available.
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- Definition Allowance for credit loss, recovery for services rendered in 2024 No definition available.
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- Definition Initial minimum percentage of cash and/or securities collateral accepted as compared to the value of securities on loan in a securities lending transaction. No definition available.
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- Definition The carrying value as of the balance sheet date of the estimated valuation allowance to reduce gross self-funded receivable to net realizable value. No definition available.
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- References No definition available.
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- Definition Amount of increase in allowance for credit loss on accounts receivable, from recovery. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition Amount of allowance for credit loss on receivable, classified as other and current. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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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 expense (reversal of expense) for expected credit loss on accounts receivable. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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- Definition The current cash, cash equivalents and investments that are restricted as to withdrawal or usage. Restrictions may include legally restricted deposits held as compensating balances against short-term borrowing arrangements, contracts entered into with others, or entity statements of intention with regard to particular deposits; however, time deposits and short-term certificates of deposit are not generally included in legally restricted deposits. Excludes compensating balance arrangements that are not agreements which legally restrict the use of cash amounts shown on the balance sheet. Includes current cash equivalents and investments that are similarly restricted as to withdrawal, usage or disposal. Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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