Pension and Other Postretirement Healthcare Benefits, Summary of Fair Value of Pension Investments (Details) - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
Change in plan assets:
Fair value of plan assets, beginning of year	$ 519
Fair value of plan assets, end of year	286	$ 519
Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	305
Fair value of plan assets, end of year	166	305
Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	116
Fair value of plan assets, end of year	57	116
Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	98
Fair value of plan assets, end of year	63	98
Global equity securities
Change in plan assets:
Fair value of plan assets, beginning of year	93
Fair value of plan assets, end of year	53	93
Global equity securities \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	93
Fair value of plan assets, end of year	53	93
Global equity securities \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Global equity securities \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Global commingled equity funds
Change in plan assets:
Fair value of plan assets, beginning of year	73
Fair value of plan assets, end of year	35	73
Global commingled equity funds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	73
Fair value of plan assets, end of year	35	73
Global commingled equity funds \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Global commingled equity funds \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
US government bonds
Change in plan assets:
Fair value of plan assets, beginning of year	81
Fair value of plan assets, end of year	48	81
US government bonds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	81
Fair value of plan assets, end of year	48	81
US government bonds \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
US government bonds \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Foreign government bonds
Change in plan assets:
Fair value of plan assets, beginning of year	39
Fair value of plan assets, end of year	19	39
Foreign government bonds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	39
Fair value of plan assets, end of year	19	39
Foreign government bonds \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Foreign government bonds \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
US corporate bonds
Change in plan assets:
Fair value of plan assets, beginning of year	73
Fair value of plan assets, end of year	34	73
US corporate bonds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
US corporate bonds \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	73
Fair value of plan assets, end of year	34	73
US corporate bonds \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Foreign corporate bonds
Change in plan assets:
Fair value of plan assets, beginning of year	42
Fair value of plan assets, end of year	22	42
Foreign corporate bonds \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Foreign corporate bonds \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	42
Fair value of plan assets, end of year	22	42
Foreign corporate bonds \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Property/ real estate fund
Change in plan assets:
Fair value of plan assets, beginning of year	1
Fair value of plan assets, end of year	1	1
Property/ real estate fund \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Property/ real estate fund \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	1
Fair value of plan assets, end of year	1	1
Property/ real estate fund \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Insurance contracts
Change in plan assets:
Fair value of plan assets, beginning of year	98
Fair value of plan assets, end of year	63	98
Insurance contracts \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Insurance contracts \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Insurance contracts \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	98	111
Actual return on plan assets	(20)	(6)
Purchases, sales, settlements	(5)	(6)
Transfers in/out of Level 3	0	0
Foreign currency rate changes	(10)	(1)
Fair value of plan assets, end of year	63	98
Cash & cash equivalents
Change in plan assets:
Fair value of plan assets, beginning of year	19
Fair value of plan assets, end of year	11	19
Cash & cash equivalents \| Quoted Prices in Active Markets for Identical Assets (Level 1)
Change in plan assets:
Fair value of plan assets, beginning of year	19
Fair value of plan assets, end of year	11	19
Cash & cash equivalents \| Significant Other Observable Inputs (Level 2)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Cash & cash equivalents \| Significant Unobservable Inputs (Level 3)
Change in plan assets:
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	$ 0	$ 0

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

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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.

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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 of foreign currency translation gain (loss) which increases (decreases) plan assets of defined benefit plan.

+ 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

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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

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