Represents the percentage of the company's total pension obligations represented within the tables provided.

No definition available.

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- Definition

Amount of future annual benefit for defined benefit plan participant covered by insurance contract. Includes, but is not limited to, contract issued by employer or its related party.

+ References

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- Definition

Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of projected benefit obligation for defined benefit pension plan with projected benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of accumulated benefit obligation for defined benefit plan with accumulated benefit obligation in excess of plan assets.

+ References

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- Definition

Amount of plan asset for defined benefit plan with accumulated benefit obligation in excess of plan assets.

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- Definition

Amount of gain (loss) recognized in net periodic benefit (cost) credit from irrevocable action relieving primary responsibility for benefit obligation and eliminating risk related to obligation and assets used to effect settlement.

+ References

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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Employee Benefits - Pension Plans Narrative (Details) £ in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2021 USD ($)	Dec. 31, 2021 GBP (£)	Dec. 31, 2020 USD ($)	Dec. 31, 2020 GBP (£)	Dec. 31, 2019 USD ($)	Dec. 31, 2019 GBP (£)	Nov. 30, 2020 USD ($)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Percentage of the Company's projected benefit obligation	90.00%
Pension Plan \| U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plans with PBO in excess of plan assets, PBO	$ 3,200		$ 3,300
Plans with ABO in excess of the fair value of plan assets, ABO	3,200		3,300
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets	2,400		2,200
Non-cash settlement charge	0		0		$ 0
Payment for settlements	0		0
Pension Plan \| U.K.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Estimated retirement benefits covered by insurance contract, impact amount							$ 94
Plans with PBO in excess of plan assets, PBO	17		54
Plans with ABO in excess of the fair value of plan assets, ABO	17		54
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets			32
Non-cash settlement charge	5	£ 3	2	£ 2	5	£ 4
Payment for settlements	14		7
Pension Plan \| Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
Plans with PBO in excess of plan assets, PBO	1,500		1,600
Plans with ABO in excess of the fair value of plan assets, ABO	409		443
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets	326		342
Plans with PBO in excess of plan assets, plan assets	1,400		1,400
Non-cash settlement charge	0		0		$ 0
Payment for settlements	$ 0		$ 0