General (Effects of Adoption of ASU 2018-12, Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2023	Sep. 30, 2022		Sep. 30, 2023	Sep. 30, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments	$ (1,085)	$ (1,737)	[1]	$ (837)	$ (6,612)
Impact of changes in discount rates used to measure long-duration contract liabilities	818	994	[1]	678	4,136
Other comprehensive loss	(316)	(840)	[1]	(143)	(2,643)
Total comprehensive income (loss)	(58)	(882)	[1]	695	(2,200)
Net unrealized gains and losses on other investments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments	$ (1,084)	(1,735)	[1]	$ (827)	(6,604)
Prior to Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		(1,329)			(4,292)
Impact of changes in discount rates used to measure long-duration contract liabilities		0			0
Other comprehensive loss		(1,426)			(4,459)
Total comprehensive income (loss)		(1,298)			(3,813)
Prior to Adoption | Net unrealized gains and losses on other investments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		(1,327)			(4,284)
Effect of Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		(408)			(2,320)
Impact of changes in discount rates used to measure long-duration contract liabilities		994			4,136
Other comprehensive loss		586			1,816
Total comprehensive income (loss)		416			1,613
Effect of Adoption | Net unrealized gains and losses on other investments
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		$ (408)			$ (2,320)

[1] As of January 1, 2023, the Company adopted ASU 2018-12 using the modified retrospective method applied as of the transition date of January 1, 2021. Prior period amounts in the financial statements have been adjusted to reflect application of the new guidance. See Note A to the Condensed Consolidated Financial Statements for additional information.