Schedule II - Cash Flow Statement (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2022		Dec. 31, 2021		Dec. 31, 2020
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	$ 4,207		$ 6,279		$ 1,038
Cash flows from investing activities:
Sales and maturities of investments	2,891		6,258		3,896
Sales of divested businesses	0		4,683		2,173
Other, net	(443)		(995)		6
Net cash used in investing activities	(3,626)		(3,280)		(6,202)
Cash flows from financing activities:
Issuance of long-term debt	7,477		107		4,196
Repayments of debt	(9,455)		(4,147)		(1,923)
Cash dividends paid on preferred stock	(29)		(29)		(29)
Cash dividends paid on common stock	(982)		(1,083)		(1,103)
Purchase of common stock	(5,200)		(2,592)		(500)
Other, net	545		1,222		541
Net cash provided by (used in) financing activities	(676)		(3,735)		5,058
Cash and restricted cash at beginning of year	2,427		3,230
Cash and restricted cash at end of year	2,216		2,427		3,230
Supplementary Disclosure of Condensed Consolidated Cash Flow Information
Cash	$ 2,043	[1]	$ 2,198	[1]	$ 2,827
Restricted Cash, Statement of Financial Position [Extensible Enumeration]	Cash		Cash		Cash
Total cash and restricted cash shown in the Consolidated Statements of Cash Flows	$ 2,216		$ 2,427		$ 3,230
Interest	1,127		1,348		1,147
Taxes	746		862		975
Short-term investments, at cost (approximates fair value)
Supplementary Disclosure of Condensed Consolidated Cash Flow Information
Restricted cash	140		197
Other assets
Supplementary Disclosure of Condensed Consolidated Cash Flow Information
Restricted cash	33		32
Parent Company
Condensed Cash Flow Statements, Captions [Line Items]
Net cash provided by (used in) operating activities	191		3,837		(30)
Cash flows from investing activities:
Sales and maturities of investments	5,205		4,228		5,181
Sales of divested businesses	0		0		2,225
Purchase of investments	(90)		(5,761)		(3,250)
Net change in short-term investments	945		2,647		(3,559)
Contributions from (to) subsidiaries - net	(330)		403		(964)
Loans to subsidiaries - net	8,427		(104)		(22)
Other, net	45		(41)		(402)
Net cash used in investing activities	14,202		1,372		(791)
Cash flows from financing activities:
Issuance of long-term debt	0		0		4,065
Repayments of debt	(9,364)		(3,703)		(1,696)
Cash dividends paid on preferred stock	(29)		(29)		(29)
Cash dividends paid on common stock	(982)		(1,083)		(1,103)
Loans from subsidiaries - net	(224)		3		16
Purchase of common stock	(5,200)		(2,598)		(500)
Other, net	1,408		2,201		(33)
Net cash provided by (used in) financing activities	(14,391)		(5,209)		720
Change in cash and restricted cash	2		0		(101)
Cash and restricted cash at beginning of year	4		4		105
Cash and restricted cash at end of year	6		4		4
Supplementary Disclosure of Condensed Consolidated Cash Flow Information
Cash	5		3		3
Restricted cash	1		1		1
Total cash and restricted cash shown in the Consolidated Statements of Cash Flows	6		4		4
Interest	(716)		(941)		(1,014)
Intercompany	63		1		0
Taxes	(348)		(494)		(466)
Intercompany	1,120		1,950		1,592
Intercompany non-cash financing and investing activities:
Capital contributions	660		2,284		333
Return of capital	0		1,365		0
Dividend received in the form of intercompany note	0		8,300		0
Dividends received in the form of securities	$ 494		$ 1,289		$ 879

[1] See Note 9 for details of balances associated with variable interest entities.