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Employee Benefits - Pension Plans Narrative (Details) £ in Millions, $ in Millions | 1 Months Ended | 12 Months Ended
--- | --- | ---
Nov. 30, 2022 USD ($) | Nov. 30, 2020 USD ($) | Dec. 31, 2022 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2021 GBP (£) | Dec. 31, 2020 USD ($) | Dec. 31, 2020 GBP (£)
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Percentage of the Company's projected benefit obligation |  |  | 88.00% |  |  |  |
U.S. |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Settlement expense |  |  | $ 170 |  |  |  |
Non-cash settlement charge |  |  | (170) |  |  |  |
Pension Plan | U.S. |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Benefits obligations settled | $ 280 |  |  |  |  |  |
Defined benefit plan, plan assets for settlements | $ 280 |  | 283 | $ 0 |  |  |
Plans with PBO in excess of plan assets, PBO |  |  | 2,200 | 3,200 |  |  |
Plans with ABO in excess of the fair value of plan assets, ABO |  |  | 2,200 | 3,200 |  |  |
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  |  | 1,500 | 2,400 |  |  |
Settlement expense |  |  | (170) | 0 |  | $ 0 |
Non-cash settlement charge |  |  | 170 | 0 |  | 0 |
Pension Plan | U.K. |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Defined benefit plan, plan assets for settlements |  |  | 0 | 14 |  |  |
Insurance contract, decrease in Prepaid pension assets |  | $ 94 |  |  |  |  |
Plans with PBO in excess of plan assets, PBO |  |  | 114 | 17 |  |  |
Plans with ABO in excess of the fair value of plan assets, ABO |  |  | 114 | 17 |  |  |
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  |  | 93 |  |  |  |
Settlement expense |  |  | 0 | (5) | £ (3) | (2) | £ (2)
Non-cash settlement charge |  |  | 0 | 5 | £ 3 | 2 | £ 2
Pension Plan | Other |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |
Defined benefit plan, plan assets for settlements |  |  | 0 | 0 |  |  |
Plans with PBO in excess of plan assets, PBO |  |  | 1,100 | 1,500 |  |  |
Plans with ABO in excess of the fair value of plan assets, ABO |  |  | 220 | 409 |  |  |
Plans with ABO in excess of the fair value of plan assets, fair value of plan assets |  |  | 166 | 326 |  |  |
Plans with PBO in excess of plan assets, plan assets |  |  | 1,000 | 1,400 |  |  |
Settlement expense |  |  | 0 | 0 |  | 0 |
Non-cash settlement charge |  |  | $ 0 | $ 0 |  | $ 0 |

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- Definition Amount of plan asset for defined benefit pension plan with projected benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2417-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI https://asc.fasb.org/extlink&oid=123450688&loc=d3e4179-114921 + Details
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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 Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h)(7) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 45 -Paragraph 3A -URI https://asc.fasb.org/extlink&oid=123453770&loc=SL108413299-114919 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a)(7) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e2709-114920 + Details
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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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b)(8) -URI https://asc.fasb.org/extlink&oid=123447040&loc=d3e1928-114920 + Details
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