Employee Benefit Plans (Significant Unobservable Inputs) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023
Pension Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	$ 8,270	$ 8,294
Purchases, sales, issuances and settlements, net	(36)	(35)
Estimated fair value of plan assets at December 31,	7,836	8,270
Pension Benefits | Foreign government
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	810
Estimated fair value of plan assets at December 31,	731	810
Pension Benefits | Other (1)
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	699
Estimated fair value of plan assets at December 31,	446	699
Pension Benefits | Equity Securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	610
Estimated fair value of plan assets at December 31,	695	610
Pension Benefits | Other investments
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	869
Estimated fair value of plan assets at December 31,	727	869
Pension Benefits | Corporate fixed maturity securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	3,083
Estimated fair value of plan assets at December 31,	3,081	3,083
Other Postretirement Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	1,334	1,303
Purchases, sales, issuances and settlements, net	(2)	0
Estimated fair value of plan assets at December 31,	1,329	1,334
Other Postretirement Benefits | Foreign government
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	46
Estimated fair value of plan assets at December 31,	38	46
Other Postretirement Benefits | Other (1)
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	37
Estimated fair value of plan assets at December 31,	66	37
Other Postretirement Benefits | Equity Securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	59
Estimated fair value of plan assets at December 31,	58	59
Other Postretirement Benefits | Other investments
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	1
Estimated fair value of plan assets at December 31,	1	1
Other Postretirement Benefits | Corporate fixed maturity securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	167
Estimated fair value of plan assets at December 31,	175	167
Level 3 | Pension Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	904
Estimated fair value of plan assets at December 31,	748	904
Level 3 | Pension Benefits | Foreign government
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	2	0
Realized gains (losses)	0	0
Unrealized gains (losses)	0	0
Purchases, sales, issuances and settlements, net	0	0
Transfers into and/or out of Level 3	0	2
Estimated fair value of plan assets at December 31,	2	2
Level 3 | Pension Benefits | Other (1)
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	8	3
Realized gains (losses)	0	0
Unrealized gains (losses)	(1)	0
Purchases, sales, issuances and settlements, net	(4)	0
Transfers into and/or out of Level 3	(1)	5
Estimated fair value of plan assets at December 31,	2	8
Level 3 | Pension Benefits | Equity Securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	12	3
Realized gains (losses)	0	0
Unrealized gains (losses)	0	1
Purchases, sales, issuances and settlements, net	(4)	8
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	8	12
Level 3 | Pension Benefits | Other investments
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	828	855
Realized gains (losses)	0	(1)
Unrealized gains (losses)	(24)	(51)
Purchases, sales, issuances and settlements, net	(124)	25
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	680	828
Level 3 | Pension Benefits | Corporate fixed maturity securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	54	55
Realized gains (losses)	0	0
Unrealized gains (losses)	(2)	1
Purchases, sales, issuances and settlements, net	16	2
Transfers into and/or out of Level 3	(12)	(4)
Estimated fair value of plan assets at December 31,	56	54
Level 3 | Pension Benefits | Derivative Financial Instruments, Assets
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0	4
Realized gains (losses)	0	0
Unrealized gains (losses)	0	(1)
Purchases, sales, issuances and settlements, net	0	(3)
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits | Foreign government
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits | Other (1)
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits | Equity Securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits | Other investments
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	0	0
Level 3 | Other Postretirement Benefits | Corporate fixed maturity securities
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	0
Estimated fair value of plan assets at December 31,	$ 0	$ 0