Date when the debt instrument is scheduled to be fully repaid, in CCYY-MM format.

No definition available.

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- Definition

Amount of write-down of assets recognized in the income statement. Includes, but is not limited to, losses from tangible assets, intangible assets and goodwill.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 28
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=109223946&loc=d3e3602-108585

Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 360
-SubTopic 10
-Section 45
-Paragraph 4
-URI http://asc.fasb.org/extlink&oid=109226348&loc=d3e2420-110228

+ Details

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- Definition

Contractual interest rate for funds borrowed, under the debt agreement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02.22(a)(1))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

+ Details

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

+ Details

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- Details

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Fair Value Measurements (Narrative) (Details) - USD ($) $ in Millions	1 Months Ended	3 Months Ended	9 Months Ended	12 Months Ended
	Jan. 31, 2015	Sep. 30, 2018	Sep. 30, 2018	Dec. 31, 2017	Jul. 31, 2018	Jul. 31, 2016
Debt Instrument [Line Items]
Impairments		$ 161	$ 161
Long-term Debt [Member] \| 4.05% Senior Notes due January 2020 [Member]
Debt Instrument [Line Items]
Stated interest rate	4.05%	4.05%	4.05%	4.05%	5.30%	5.80%
Maturity date, year and month	2020-01		2020-01	2020-01
Gathering Assets Held for Sale [Member]
Debt Instrument [Line Items]
Impairments		$ 145	$ 145
E&P Assets Held for Sale [Member]
Debt Instrument [Line Items]
Impairments		15	15
Other Non-Core Assets [Member]
Debt Instrument [Line Items]
Impairments		$ 1	$ 1