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Lease Commitments - Cash Flow of Lessee (Details) $ in Millions | 12 Months Ended
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Dec. 31, 2019 USD ($)
Cash paid for amounts included in the measurement of lease liabilities |
Operating cash flows for operating leases | $ 264
Financing cash flows for finance leases | 17
Non-cash related activities |
ROU assets obtained in exchange for new operating lease liabilities | 155
ROU assets obtained in exchange for new finance lease liabilities | 48
Operating lease ROU asset expense | 195
Changes in Non-current operating lease liabilities | $ (70)

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- Definition Amount of cash outflow for principal payment on finance lease. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 45 -Paragraph 5 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977 Reference 2: http://www.xbrl.org/2003/role/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 842 -SubTopic 20 -Section 50 -Paragraph 4 -Subparagraph (g)(1) -URI http://asc.fasb.org/extlink&oid=77888426&loc=SL77918686-209980 + Details
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