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Leases (Supplemental balance sheet) (Details) - USD ($) $ in Millions | Dec. 31, 2021 | Dec. 31, 2020 | Dec. 31, 2019
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Leases [Abstract] |  |  |
Right-of-use (ROU) assets | $ 317 | $ 306 | $ 329
Operating lease liabilities | $ 356 | $ 344 | $ 367
Weighted average discount rate | 3.33% | 3.61% | 3.78%
Weighted average lease term in years | 8 years | 8 years | 9 years

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- Definition Lessee, operating lease, liability, to be paid less interest + References No definition available. + Details
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- Definition Right-of -use (ROU) assets + References No definition available. + Details
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Balance Type: | debit
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- References No definition available. + Details
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- Definition Discount rate used by lessee to determine present value of operating lease payments. + References Reference 1: http://www.xbrl.org/2003/role/exampleRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (c)(3) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980 + Details
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- Definition Term of lessee's operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. + References Reference 1: http://www.xbrl.org/2009/role/commonPracticeRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (a)(3) -URI http://asc.fasb.org/extlink&oid=123408670&loc=SL77918673-209980 + Details
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