Leases Components of balance sheet (Details) - USD ($) $ in Millions	Dec. 31, 2019	Dec. 31, 2018
Operating lease right-of-use assets (non-current)	$ 931	$ 0
Current portion of operating lease liabliities	208	0
Operating lease liabilities (non-current)	825	$ 0
Other assets
Finance leases - Other assets (non-current)	123
Other current liabilities
Finance leases - Other current liabilities	19
Other liabilities
Finance leases - Other liabilities (non-current)	$ 124

Present value of lessee's discounted obligation for lease payments from finance lease, classified as current.

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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Reference 1: http://www.xbrl.org/2003/role/disclosureRef
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-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
-Section 45
-Paragraph 1
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918627-209977

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