Employee Benefit Plans (Significant Unobservable Inputs) (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2021	Dec. 31, 2020
Pension Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	$ 11,256	$ 10,230
Purchases, sales, issuances and settlements, net	(35)	(55)
Estimated fair value of plan assets at December 31,	10,971	11,256
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,	990
Estimated fair value of plan assets at December 31,	1,116	990
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,	1,156
Estimated fair value of plan assets at December 31,	783	1,156
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,	1,101
Estimated fair value of plan assets at December 31,	895	1,101
Other Postretirement Benefits
Rollforward fair value measurement using significant unobservable inputs (level 3) [Roll Forward]
Estimated fair value of plan assets at January 1,	1,492	1,468
Purchases, sales, issuances and settlements, net	(1)	0
Estimated fair value of plan assets at December 31,	1,443	1,492
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,	69
Estimated fair value of plan assets at December 31,	51	69
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,	88
Estimated fair value of plan assets at December 31,	59	88
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,	56
Estimated fair value of plan assets at December 31,	55	56
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,	708
Estimated fair value of plan assets at December 31,	967	708
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,	0	0
Realized gains (losses)	0	0
Unrealized gains (losses)	0	0
Purchases, sales, issuances and settlements, net	1	0
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	1	0
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,	0	3
Realized gains (losses)	0	0
Unrealized gains (losses)	0	0
Purchases, sales, issuances and settlements, net	1	(3)
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	1	0
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,	0	0
Realized gains (losses)	0	0
Unrealized gains (losses)	0	0
Purchases, sales, issuances and settlements, net	11	0
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	11	0
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,	708	686
Realized gains (losses)	0	0
Unrealized gains (losses)	63	(55)
Purchases, sales, issuances and settlements, net	183	77
Transfers into and/or out of Level 3	0	0
Estimated fair value of plan assets at December 31,	954	708
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

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets sold.

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan from actual return (loss) on assets still held.

+ References

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

+ References

No definition available.

+ Details

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- Definition

Amount of asset segregated and restricted to provide benefit under defined benefit plan. Asset includes, but is not limited to, stock, bond, other investment, earning from investment, and contribution by employer and employee.

+ References

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- Definition

Amount, measured using unobservable input, of increase (decrease) in plan asset of defined benefit plan from purchase, sale and settlement of trade associated with underlying investment.

+ References

+ Details

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- Definition

Amount, measured using unobservable inputs, of increase (decrease) in plan assets of defined benefit plan, for assets transferred into (out of) Level 3 of fair value hierarchy. Includes, but is not limited to, transfer due to change in observability of significant inputs.

+ References

+ Details

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