Leases - Maturities of lease liabilities (Details) $ in Millions	Dec. 31, 2019 USD ($)
Operating leases
2020	$ 42
2021	40
2022	30
2023	27
2024	25
Thereafter	117
Less: imputed interest	(68)
Total minimum lease payments	213
Finance leases
2020	2
2021	1
2022	1
Less: imputed interest	(1)
Total minimum lease payments	$ 3

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Present value of lessee's discounted obligation for lease payments from finance 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=77888426&loc=SL77918701-209980

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-Publisher FASB
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-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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Amount of lessee's undiscounted obligation for lease payments for finance lease, due in next fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due after fifth fiscal year following latest fiscal year.

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Amount of lessee's undiscounted obligation for lease payments for operating lease, due in fourth fiscal year following latest fiscal year.

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+ References

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-Publisher FASB
-Name Accounting Standards Codification
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