Leases, Supplemental Cash Flow and Other Information (Details) - USD ($) $ in Millions	9 Months Ended
Sep. 30, 2020	Sep. 30, 2019
Lessee Disclosure [Abstract]
Operating Lease, Payments	$ 20	$ 18
Finance Lease, Interest Payment on Liability	3	0
Finance Lease, Principal Payments	1	0
Right-of-Use Asset Obtained in Exchange for Operating Lease Liability	6	33
Right-of-Use Asset Obtained in Exchange for Finance Lease Liability	$ 5	$ 5
Operating Lease, Weighted Average Remaining Lease Term	6 years	5 years
Finance Lease, Weighted Average Remaining Lease Term	5 years	5 years
Operating Lease, Weighted Average Discount Rate, Percent	4.00%	4.00%
Finance Lease, Weighted Average Discount Rate, Percent	3.00%	4.00%

Amount of interest paid on finance lease liability.

Reference 1: 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

Reference 2: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
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-Paragraph 5
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-URI http://asc.fasb.org/extlink&oid=77888419&loc=SL77918643-209977

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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
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-SubTopic 20
-Section 45
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Weighted average discount rate for finance lease calculated at point in time.

+ References

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-Publisher FASB
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Weighted average remaining lease term for finance 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/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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-Paragraph 4
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- References

No definition available.

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Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use.

+ References

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-Publisher FASB
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Weighted average discount rate for operating lease calculated at point in time.

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Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days.

+ References

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Amount of increase in right-of-use asset obtained in exchange for finance lease liability.

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Amount of increase in right-of-use asset obtained in exchange for operating lease liability.

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