Employee Benefits - Schedule of changes in Level 3 plan assets measured at fair value (Details) - Pension - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2023	Dec. 31, 2022
U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	$ 3,345	$ 4,746
Fair value of plan assets, end of year	3,228	3,345
Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	731	996
Fair value of plan assets, end of year	734	731
Level 3 \| U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	20	25
Net Realized and Unrealized Gains (Losses)	(4)	(6)
Purchases	0	7
Sales	(5)	(2)
Issuances	0	0
Settlements	0	0
Transfers In	0	2
Transfers Out	0	(6)
Fair value of plan assets, end of year	11	20
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(3)	(7)
Level 3 \| U.S. Plans \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Level 3 \| Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	134	171
Net Realized and Unrealized Gains (Losses)	6	(43)
Purchases	1	4
Sales	0	0
Issuances	0	0
Settlements	(3)	0
Transfers In	0	2
Transfers Out	0	0
Fair value of plan assets, end of year	138	134
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Level 3 \| Foreign Plan \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Direct private equity \| Level 3 \| U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	5	8
Net Realized and Unrealized Gains (Losses)	(5)	(1)
Purchases	0	0
Sales	0	(2)
Issuances	0	0
Settlements	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	0	5
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(5)	(2)
Direct private equity \| Level 3 \| U.S. Plans \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Fixed maturity securities \| U.S. investment grade \| Level 3 \| U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	10	16
Net Realized and Unrealized Gains (Losses)	1	(4)
Purchases	0	4
Sales	(1)	0
Issuances	0	0
Settlements	0	0
Transfers In	0	0
Transfers Out	0	(6)
Fair value of plan assets, end of year	10	10
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	1	(4)
Fixed maturity securities \| U.S. investment grade \| Level 3 \| U.S. Plans \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Fixed maturity securities \| U.S. investment grade \| Level 3 \| Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Fixed maturity securities \| Mortgage-backed, asset-backed and collateralized \| Level 3 \| U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	5	1
Net Realized and Unrealized Gains (Losses)	0	(1)
Purchases	0	3
Sales	(4)	0
Issuances	0	0
Settlements	0	0
Transfers In	0	2
Transfers Out	0	0
Fair value of plan assets, end of year	1	5
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	1	(1)
Fixed maturity securities \| Mortgage-backed, asset-backed and collateralized \| Level 3 \| U.S. Plans \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Fixed maturity securities \| Mortgage-backed, asset-backed and collateralized \| Level 3 \| Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	0
Fair value of plan assets, end of year	0	0
Insurance contracts \| Level 3 \| Foreign Plan
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	134	171
Net Realized and Unrealized Gains (Losses)	6	(43)
Purchases	1	4
Sales	0	0
Issuances	0	0
Settlements	(3)	0
Transfers In	0	2
Transfers Out	0	0
Fair value of plan assets, end of year	138	134
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Insurance contracts \| Level 3 \| Foreign Plan \| Other Comprehensive Income (Loss)
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	$ 0	$ 0

Defined Benefit Plan Actual Return On Plan Assets During Period

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- Definition

Defined Benefit Plan Plan Assets Level 3 Reconciliation Increase Decrease For Purchase

+ References

No definition available.

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- Definition

Defined Benefit Plan, Plan Assets Level 3 Reconciliation Increase For Issuances

+ References

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- Definition

Defined Benefit Plan Transfers In

+ References

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- Definition

Defined Benefit Plan Transfers Out

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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.

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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

Reference 1: http://www.xbrl.org/2003/role/exampleRef
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- Definition

Amount, measured using unobservable input, of decrease in plan asset of defined benefit plan from sale.

+ References

Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef
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- Definition

Amount, measured using unobservable input, of decrease in plan asset of defined benefit plan from settlement of trade associated with underlying investment.

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