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Leases (Details) - USD ($) $ in Millions | 12 Months Ended
--- | ---
Dec. 31, 2020 | Dec. 31, 2019
Assets and Liabilities, Lessee [Abstract] |  |
Operating lease right-of-use assets | $ 461 | $ 443
Operating Lease, Liability, Current, Statement of Financial Position [Extensible List] | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent | us-gaap:AccountsPayableAndAccruedLiabilitiesCurrent
Operating Lease, Liability, Current | $ 89 | $ 93
Operating lease liabilities | 376 | 355
Operating Lease, Liability | $ 465 | $ 448
Operating Lease, Weighted Average Remaining Lease Term | 8 years | 8 years
Operating Lease, Weighted Average Discount Rate, Percent | 3.10% | 3.50%
Lease, Cost [Abstract] |  |
Operating Lease, Cost | $ 117 | $ 113
Short-term Lease, Cost | 70 | 58
Lease, Cost | 187 | 171
Operating Leased Assets [Line Items] |  |
Lessee, Operating Lease, Liability, Payments, Due Next Twelve Months | 102 |
Lessee, Operating Lease, Liability, Payments, Due Year Two | 85 |
Lessee, Operating Lease, Liability, Payments, Due Year Three | 69 |
Lessee, Operating Lease, Liability, Payments, Due Year Four | 54 |
Lessee, Operating Lease, Liability, Payments, Due Year Five | 42 |
Lessee, Operating Lease, Liability, Payments, Due after Year Five | 171 |
Lessee, Operating Lease, Liability, Payments, Due | 523 |
Lessee, Operating Lease, Liability, Undiscounted Excess Amount | (58) |
Fixed Lease Payments [Member] | Affiliates [Member] |  |
Lease, Cost [Abstract] |  |
Operating Lease, Cost | 12 | 18
Affiliates [Member] |  |
Assets and Liabilities, Lessee [Abstract] |  |
Operating lease right-of-use assets | $ 41 | $ 50

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- Definition Amount of lease cost recognized by lessee for lease contract. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease due after fifth fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in next fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980 + Details
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- Definition Amount of lessee's undiscounted obligation for lease payment for operating lease to be paid in third fiscal year following current fiscal year. Excludes interim and annual periods when interim periods are reported from current statement of financial position date (rolling approach). + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 6 -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918701-209980 + Details
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- Definition Amount of single lease cost, calculated by allocation of remaining cost of lease over remaining lease term. Includes, but is not limited to, single lease cost, after impairment of right-of-use asset, calculated by amortization of remaining right-of-use asset and accretion of lease liability. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 55 -Paragraph 53 -URI http://asc.fasb.org/extlink&oid=121568110&loc=SL77918982-209971 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=121609121&loc=SL77918686-209980 + Details
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