Employee Benefits - Estimated Future Benefit Payments (Details) - Pension Plan $ in Millions	Dec. 31, 2024 USD ($)
U.K.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	$ 167
2026	172
2027	177
2028	182
2029	186
2030 - 2034	974
Other
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	45
2026	46
2027	48
2028	49
2029	50
2030 - 2034	267
U.S.
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items]
2025	163
2026	166
2027	167
2028	168
2029	158
2030 - 2034	$ 747

Amount of benefit for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following current fiscal year.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Topic 715
-SubTopic 20
-Name Accounting Standards Codification
-Section 50
-Paragraph 1
-Subparagraph (f)
-Publisher FASB
-URI https://asc.fasb.org/1943274/2147480506/715-20-50-1

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Amount of benefit for defined benefit plan expected to be paid in next fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fifth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in fourth fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in third fiscal year following current fiscal year.

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Amount of benefit for defined benefit plan expected to be paid in second fiscal year following current fiscal year.

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