Investments (Securities Lending) (Details) - USD ($) $ in Millions	Mar. 31, 2024	Dec. 31, 2023
Securities Financing Transaction [Line Items]
Cash collateral received from counterparties	$ 3,191	$ 3,277
Reinvestment portfolio — estimated fair value	3,159	3,246
Amortized cost
Securities Financing Transaction [Line Items]
Securities on loan	3,441	3,420
Estimated fair value
Securities Financing Transaction [Line Items]
Securities on loan	$ 3,120	$ 3,194

This element represents the estimated fair value of the securities lending reinvestment portfolio.

No definition available.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Definition

Amount, after the effects of master netting arrangements, of securities loaned to entities in exchange for collateral. Includes liabilities not subject to a master netting arrangement and not elected to be offset.

+ References

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- Definition

Carrying amount of liabilities associated with financial assets accounted for as secured borrowings recognized in the transferor's statement of financial position at the end of each period presented.

+ References

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