Employee Benefits - Schedule of changes in Level 3 plan assets measured at fair value (Details) - Pension - USD ($) $ in Millions	12 Months Ended
Dec. 31, 2022	Dec. 31, 2021
U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	$ 4,746	$ 4,931
Fair value of plan assets, end of year	3,345	4,746
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	25	16
Net Realized and Unrealized Gains (Losses)	(6)	2
Purchases	7	6
Sales	(2)	(4)
Issuances	0	0
Settlements	0	0
Transfers In	2	5
Transfers Out	(6)	0
Fair value of plan assets, end of year	20	25
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(7)	1
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 \| Non-U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	171	179
Net Realized and Unrealized Gains (Losses)	(43)	(9)
Purchases	4	1
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers In	2	0
Transfers Out	0	0
Fair value of plan assets, end of year	134	171
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Level 3 \| Non-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
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	8	6
Net Realized and Unrealized Gains (Losses)	(1)	2
Purchases	0	0
Sales	(2)	0
Issuances	0	0
Settlements	0	0
Transfers In	0	0
Transfers Out	0	0
Fair value of plan assets, end of year	5	8
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(2)	1
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	16	10
Net Realized and Unrealized Gains (Losses)	(4)	0
Purchases	4	5
Sales	0	(4)
Issuances	0	0
Settlements	0	0
Transfers In	0	5
Transfers Out	(6)	0
Fair value of plan assets, end of year	10	16
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(4)	0
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 \| Non-U.S. Plans
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	1	0
Net Realized and Unrealized Gains (Losses)	(1)	0
Purchases	3	1
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers In	2	0
Transfers Out	0	0
Fair value of plan assets, end of year	5	1
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	(1)	0
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 \| Non-U.S. Plans
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 \| Non-U.S. Plans
Defined Benefit Plan, Change in Fair Value of Plan Assets [Roll Forward]
Fair value of plan assets, beginning of year	171	179
Net Realized and Unrealized Gains (Losses)	(43)	(9)
Purchases	4	1
Sales	0	0
Issuances	0	0
Settlements	0	0
Transfers In	2	0
Transfers Out	0	0
Fair value of plan assets, end of year	134	171
Changes in Unrealized Gains (Losses) on Instruments Held at End of Year	0	0
Insurance contracts \| Level 3 \| Non-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

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

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- Definition

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

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- Definition

Defined Benefit Plan Transfers In

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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.

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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.

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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/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 20
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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
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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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