General (Effects of Adoption of ASU 2018-12, Comprehensive Income (Loss)) (Details) - USD ($) $ in Millions	3 Months Ended			6 Months Ended
	Jun. 30, 2023	Jun. 30, 2022		Jun. 30, 2023	Jun. 30, 2022
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments	$ (414)	$ (2,228)	[1]	$ 248	$ (4,875)
Impact of changes in discount rates used to measure long-duration contract liabilities	256	1,507	[1]	(140)	3,142
Other comprehensive income (loss)	(117)	(783)	[1]	173	(1,803)
Total comprehensive income (loss)	166	(593)	[1]	753	(1,318)
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	$ (413)	(2,226)	[1]	$ 257	(4,869)
Prior to Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		(1,348)			(2,963)
Impact of changes in discount rates used to measure long-duration contract liabilities		0			0
Other comprehensive income (loss)		(1,410)			(3,033)
Total comprehensive income (loss)		(1,205)			(2,515)
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		(1,346)			(2,957)
Effect of Adoption
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Net unrealized gains and losses on investments		(880)			(1,912)
Impact of changes in discount rates used to measure long-duration contract liabilities		1,507			3,142
Other comprehensive income (loss)		627			1,230
Total comprehensive income (loss)		612			1,197
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		$ (880)			$ (1,912)

[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.