v3.20.2

Pension and Other Postretirement Benefits - Narrative (Details) $ in Millions |  | 1 Months Ended | 3 Months Ended | 6 Months Ended | 9 Months Ended | 12 Months Ended |  |  |  |
--- | --- | --- | --- | --- | --- | --- | --- | --- | --- | ---
Jan. 01, 2020 USD ($) | Jun. 30, 2020 USD ($) | Sep. 30, 2020 USD ($) participants | Jun. 30, 2020 USD ($) | Sep. 30, 2019 USD ($) | Sep. 30, 2020 USD ($) participants | Sep. 30, 2020 USD ($) participants | Sep. 30, 2019 USD ($) | Dec. 31, 2021 USD ($) | Dec. 31, 2020 USD ($) | Jul. 31, 2020 | Jun. 01, 2020 participants | Apr. 01, 2020 USD ($) | Dec. 31, 2019
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retirement plans, liability | $ 1,920 |  |  |  |  |  |  |  |  |  |  |  |  |
Retirement plans, current liability | 60 |  |  |  |  |  |  |  |  |  |  |  |  |
Retirement plans, benefit obligation | 4,255 |  |  |  |  |  |  |  |  |  |  |  |  |
Retirement plans, plan assets | 2,335 |  |  |  |  |  |  |  |  |  |  |  |  |
Establishment of retirement plans, AOCI | $ 1,752 |  |  |  |  | $ 50 |  |  |  |  |  |  |  |
Expected employer contributions, 2020 |  |  | $ 280 |  |  | 280 | $ 280 |  |  |  |  |  |  |
Liability, Defined Benefit Plan, Noncurrent |  |  |  |  |  |  |  |  |  |  |  |  | $ 15 |
asset, defined benefit plan |  |  |  |  |  |  |  |  |  |  |  |  | $ 65 |
Liability, Other Postretirement Defined Benefit Plan |  |  | 7 |  |  | 7 | 7 |  |  |  |  |  |  |
Other Comprehensive (Income) Loss, Defined Benefit Plan, Reclassification Adjustment from AOCI, after Tax |  |  | 5 |  |  |  |  |  |  |  |  |  |  |
U.K. Defined Benefit Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement |  |  |  |  |  |  | 250 |  |  |  |  |  |  |
Forecast |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic benefit cost |  |  |  |  |  |  |  |  |  | $ 100 |  |  |  |
Service cost |  |  |  |  |  |  |  |  |  | $ 25 |  |  |  |
Payment for Pension and Other Postretirement Benefits |  |  |  |  |  |  |  |  | $ 20 |  |  |  |  |
Pension benefits |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic benefit cost |  |  | 25 |  | $ 1 |  | 119 | $ 4 |  |  |  |  |  |
Service cost |  |  | 6 |  | 1 |  | 16 | 2 |  |  |  |  |  |
Multiemployer contribution expense |  |  | 0 |  | 16 |  | 0 | 46 |  |  |  |  |  |
Expected employer contributions, 2020 |  |  | 260 |  |  | 260 | 260 |  |  |  |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  | 1.55% |  | 1.55% |  |  |  |  |  |  |  |  |  | 2.05%
Other postretirement benefits |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Net periodic benefit cost |  |  | 5 |  | 0 |  | 17 | 0 |  |  |  |  |  |
Service cost |  |  | 1 |  | 0 |  | 3 | 0 |  |  |  |  |  |
Multiemployer contribution expense |  |  | 0 |  | $ 4 |  | 0 | $ 15 |  |  |  |  |  |
Expected employer contributions, 2020 |  |  | 55 |  |  | 55 | 55 |  |  |  |  |  |  |
Defined Benefit Plan, Assumptions Used Calculating Benefit Obligation, Discount Rate |  |  |  |  |  |  |  |  |  |  | 2.54% |  |  | 3.17%
Other Pension Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Expected employer contributions, 2020 |  |  | 10 |  |  | 10 | 10 |  |  |  |  |  |  |
U.K. Defined Benefit Plan [Member] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Retirement plans, benefit obligation |  |  | 240 |  |  | 240 | 240 |  |  |  |  |  |  |
Retirement plans, plan assets |  |  | $ 260 |  |  | $ 260 | $ 260 |  |  |  |  |  |  |
Defined Benefit Plan, Participants | participants |  |  | 1,050 |  |  | 1,050 | 1,050 |  |  |  |  | 1,800 |  |
Defined Benefit Plan, Plan Assets, Contributions by Employer |  |  |  | $ 10 |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Remeasurement due to Settlement |  |  | $ 3 |  |  |  | $ 58 |  |  |  |  |  |  |
U.K. Defined Benefit Plan [Member] | ParentCo |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |  |  |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Participants | participants |  |  |  |  |  |  |  |  |  |  |  | 3,350 |  |
Defined Benefit Plan, Benefit Obligation, (Increase) Decrease for Settlement |  | $ 400 |  |  |  |  |  |  |  |  |  |  |  |
Defined Benefit Plan, Plan Assets, Increase (Decrease) for Assets Transferred to (from) Plan |  | $ 460 |  |  |  |  |  |  |  |  |  |  |  |

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- Definition Weighted average rate for present value of future retirement benefits cash flows, used to determine benefit obligation of defined benefit plan. + 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 (k)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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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 -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(01) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 4: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 5: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(iv)(02) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 6: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 7: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (d)(ii) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 6 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 Reference 3: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4587-114921 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (h) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 + Details
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- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. + 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)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 17 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4179-114921 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)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e2709-114920 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 1 -Subparagraph (a)(1) -URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920 Reference 5: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 55 -Paragraph 18 -URI http://asc.fasb.org/extlink&oid=118257860&loc=d3e4587-114921 + Details
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- Definition Amount, before tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 11 -URI http://asc.fasb.org/extlink&oid=121641772&loc=d3e637-108580 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 220 -SubTopic 10 -Section 45 -Paragraph 10A -Subparagraph (i-k) -URI http://asc.fasb.org/extlink&oid=121641772&loc=SL7669646-108580 + Details
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