No definition available.

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- Definition

Carrying amount of an asset that is legally restricted for purposes of settling an asset retirement obligation.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 410
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (b)
-URI http://asc.fasb.org/extlink&oid=6392692&loc=d3e7535-110849

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- Definition

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
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Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
-Subparagraph (c)(2)
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 50
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-Publisher FASB
-Name Accounting Standards Codification
-Topic 815
-SubTopic 10
-Section 50
-Paragraph 4B
-Subparagraph (a),(c)
-URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624163-113959

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- Definition

Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 860
-SubTopic 20
-Section 50
-Paragraph 4D
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-Publisher FASB
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Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 20
-Section 55
-Paragraph 7
-URI http://asc.fasb.org/extlink&oid=99393222&loc=SL20226000-175313

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- References

No definition available.

+ Details

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 1 of the fair value hierarchy into Level 2.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 820
-SubTopic 10
-Section 50
-Paragraph 2
-Subparagraph (bb)
-URI http://asc.fasb.org/extlink&oid=117815213&loc=d3e19207-110258

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- Definition

Amount of transfers of assets measured on a recurring basis out of Level 2 of the fair value hierarchy into Level 1.

+ References

+ Details

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 4
-Subparagraph (b)(1)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12069-110248

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- Definition

Fair value portion of guarantee, including, but not limited to, financial standby letter of credit, fair value guarantee, guarantee of collection of scheduled contractual cash flows from financial assets, and contracts that contingently require the guarantor to make payments or perform services.

+ References

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 460
-SubTopic 10
-Section 50
-Paragraph 5
-Subparagraph (a)
-URI http://asc.fasb.org/extlink&oid=118943654&loc=d3e12201-110248

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Period Type:	instant

- Definition

The fair value amount of long-term debt whether such amount is presented as a separate caption or as a parenthetical disclosure. Additionally, this element may be used in connection with the fair value disclosures required in the footnote disclosures to the financial statements. The element may be used in both the balance sheet and disclosure in the same submission.

+ References

No definition available.

+ Details

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Fair Value Measurements and Guarantees Recurring Measurements and Additional (Details) - USD ($) $ in Millions	Sep. 30, 2019	Dec. 31, 2018	Sep. 30, 2018
Additional disclosures:
Fair Value, Level 1 to level 2 Transfers, Amount	$ 0		$ 0
Fair Value, Level 2 to level 1 Transfers, Amount	0		$ 0
Carrying Amount [Member]
Additional disclosures:
Long-term debt, including current portion	(22,257)	$ (22,414)
Guarantees	(42)	(43)
Fair Value [Member]
Additional disclosures:
Long-term debt, including current portion	(25,234)	(23,330)
Guarantees	(29)	(30)
Level 1 [Member]
Additional disclosures:
Long-term debt, including current portion	0	0
Guarantees	0	0
Level 2 [Member]
Additional disclosures:
Long-term debt, including current portion	(25,234)	(23,330)
Guarantees	(13)	(14)
Level 3 [Member]
Additional disclosures:
Long-term debt, including current portion	0	0
Guarantees	(16)	(16)
Fair Value, Recurring [Member] \| Carrying Amount [Member]
Measured on a recurring basis:
ARO Trust investments	187	150
Fair Value, Recurring [Member] \| Carrying Amount [Member] \| Not Designated as Hedging Instrument [Member]
Measured on a recurring basis:
Energy derivatives assets	4	3
Energy derivatives liabilities	(5)	(7)
Fair Value, Recurring [Member] \| Fair Value [Member]
Measured on a recurring basis:
ARO Trust investments	187	150
Fair Value, Recurring [Member] \| Fair Value [Member] \| Not Designated as Hedging Instrument [Member]
Measured on a recurring basis:
Energy derivatives assets	4	3
Energy derivatives liabilities	(5)	(7)
Fair Value, Recurring [Member] \| Level 1 [Member]
Measured on a recurring basis:
ARO Trust investments	187	150
Fair Value, Recurring [Member] \| Level 1 [Member] \| Not Designated as Hedging Instrument [Member]
Measured on a recurring basis:
Energy derivatives assets	4	3
Energy derivatives liabilities	(2)	(4)
Fair Value, Recurring [Member] \| Level 2 [Member]
Measured on a recurring basis:
ARO Trust investments	0	0
Fair Value, Recurring [Member] \| Level 2 [Member] \| Not Designated as Hedging Instrument [Member]
Measured on a recurring basis:
Energy derivatives assets	0	0
Energy derivatives liabilities	0	0
Fair Value, Recurring [Member] \| Level 3 [Member]
Measured on a recurring basis:
ARO Trust investments	0	0
Fair Value, Recurring [Member] \| Level 3 [Member] \| Not Designated as Hedging Instrument [Member]
Measured on a recurring basis:
Energy derivatives assets	0	0
Energy derivatives liabilities	(3)	$ (3)
WilTel Guarantee [Member]
Additional disclosures:
Guarantor Obligations, Maximum Exposure, Undiscounted	28
Indemnification Agreement [Member] \| Carrying Amount [Member]
Additional disclosures:
Guarantees	$ 0