Debt Instrument, Accelerated Maturity Month And Year If Not Amended, Redeemed Or Refinanced

No definition available.

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- Definition

Debt Instrument, Amount To Be Amended, Redeemed Or Refinanced To Avoid Acceleration

+ References

No definition available.

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- Definition

Increase in percentage points added to the reference rate to compute the variable rate on the debt instrument.

+ References

No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.5-02(22))
-URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682

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-Publisher FASB
-Name Accounting Standards Codification
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-Section S99
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-URI http://asc.fasb.org/extlink&oid=6879938&loc=d3e572229-122910

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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

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- Definition

The average effective interest rate during the reporting period.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
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-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28551-108399

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- Definition

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

+ References

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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.

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- Definition

Amount, after accumulated amortization, of debt discount.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
-Section 45
-Paragraph 1A
-URI http://asc.fasb.org/extlink&oid=64930785&loc=d3e28541-108399

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- Definition

Difference between the fair value of payments made and the carrying amount of debt which is extinguished prior to maturity.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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-SubTopic 50
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- Definition

Amount, after unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but not limited to, notes payable, bonds payable, debentures, mortgage loans and commercial paper. Excludes capital lease obligations.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 944
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.7-03(a)(16))
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- Definition

The cash outflow for debt initially having maturity due after one year or beyond the normal operating cycle, if longer.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 230
-SubTopic 10
-Section 45
-Paragraph 15
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- Definition

The cash outflow for a borrowing having initial term of repayment within one year or the normal operating cycle, if longer.

+ References

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- Definition

The remaining balance of debt issuance expenses that were capitalized and are being amortized against income over the lives of the respective bond issues. This does not include the amounts capitalized as part of the cost of the utility plant or asset.

+ References

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Debt (Components of Debt) (Details) - USD ($) $ in Millions	1 Months Ended				6 Months Ended	12 Months Ended
Debt (Components of Debt) (Details) - USD ($) $ in Millions	Sep. 30, 2017	Sep. 30, 2016	Jul. 31, 2016	Jan. 31, 2015	Jun. 30, 2017	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Debt Instrument [Line Items]
Debt Instrument						$ 4,433	$ 4,684
Unamortized Issuance Expense							(28)
Unamortized Debt Discount							(3)
Total							4,653
Repayment of short-term debt								$ 4,500
Repayments of long-term debt						1,139	1,175	500
Loss on extinguishment of debt	$ 59				$ (11)	(70)	(51)
Short-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument							41
Total							41
Short-term Debt [Member] \| 7.35% Senior Notes due October 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument							15
Total							$ 15
Stated interest rate							7.35%
Maturity date, year and month							2017-10
Repayment of short-term debt						15
Short-term Debt [Member] \| 7.125% Senior Notes due October 2017 [Member]
Debt Instrument [Line Items]
Debt Instrument							$ 25
Total							$ 25
Stated interest rate							7.125%
Maturity date, year and month							2017-10
Repayment of short-term debt						25
Short-term Debt [Member] \| 7.15% Senior Notes due June 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument							$ 1
Total							$ 1
Stated interest rate							7.15%
Maturity date, year and month							2018-06
Long-term Debt [Member]
Debt Instrument [Line Items]
Debt Instrument						4,433	$ 4,643
Unamortized Issuance Expense						(40)	(28)	$ (24)
Unamortized Debt Discount						(2)	(3)
Total						$ 4,391	4,612
Long-term Debt [Member] \| 2015 Term Loan due December 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument							327
Unamortized Issuance Expense							(2)
Total							$ 325
Variable interest rate							3.22%
Maturity date, year and month						2020-12	2020-12
Repayments of long-term debt	327	$ 48	$ 375			$ 327	$ 423
Accelerated maturity date, year and month if not amended, redeemed or refinanced						2019-10
Long-term Debt [Member] \| 2016 Term Loan due December 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument						$ 1,191	1,191
Unamortized Issuance Expense						(8)	(10)
Unamortized Debt Discount
Total						$ 1,183	$ 1,181
Variable interest rate						3.98%	3.22%
Maturity date, year and month						2020-12	2020-12
Accelerated maturity date, year and month if not amended, redeemed or refinanced						2019-10
Long-term Debt [Member] \| 3.30% Senior Notes due January 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument							$ 38
Total							$ 38
Stated interest rate			5.05%	3.30%			3.30%
Maturity date, year and month				2018-01			2018-01
Repayments of long-term debt					$ 38	$ 38
Long-term Debt [Member] \| 7.50% Senior Notes due February 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument							$ 212
Total							$ 212
Stated interest rate					7.50%		7.50%
Maturity date, year and month					2018-02		2018-02
Repayments of long-term debt					$ 212	212
Long-term Debt [Member] \| 7.15% Senior Notes due June 2018 [Member]
Debt Instrument [Line Items]
Debt Instrument							$ 25
Total							$ 25
Stated interest rate					7.15%		7.15%
Maturity date, year and month					2018-06		2018-06
Repayments of long-term debt					$ 26	26
Long-term Debt [Member] \| 4.05% Senior Notes due January 2020 [Member]
Debt Instrument [Line Items]
Debt Instrument						92	$ 850
Unamortized Issuance Expense							(5)
Unamortized Debt Discount
Total						$ 92	$ 845
Stated interest rate			5.80%	4.05%		4.05%	4.05%
Maturity date, year and month				2020-01		2020-01	2020-01
Repayments of long-term debt	$ 758					$ 758
Amount to be amended, redeemed or refinanced to avoid acceleration						765	$ 765
Long-term Debt [Member] \| 4.10% Senior Notes due March 2022 [Member]
Debt Instrument [Line Items]
Debt Instrument						1,000	1,000
Unamortized Issuance Expense						(7)	(4)
Unamortized Debt Discount							(1)
Total						$ 993	$ 995
Stated interest rate						4.10%	4.10%
Maturity date, year and month						2022-03	2022-03
Long-term Debt [Member] \| 4.95% Senior Notes due January 2025 [Member]
Debt Instrument [Line Items]
Debt Instrument						$ 1,000	$ 1,000
Unamortized Issuance Expense						(8)	(7)
Unamortized Debt Discount						(2)	(2)
Total						$ 990	$ 991
Stated interest rate			6.70%	4.95%		4.95%	4.95%
Maturity date, year and month				2025-01		2025-01	2025-01
Long-term Debt [Member] \| 7.50% Senior Notes due April 2026 [Member]
Debt Instrument [Line Items]
Debt Instrument						$ 650
Unamortized Issuance Expense						(10)
Unamortized Debt Discount
Total						$ 640
Stated interest rate	7.50%					7.50%
Maturity date, year and month	2026-04					2026-04
Long-term Debt [Member] \| 7.75% Senior Notes due October 2027 [Member]
Debt Instrument [Line Items]
Debt Instrument						$ 500
Unamortized Issuance Expense						(7)
Unamortized Debt Discount
Total						$ 493
Stated interest rate	7.75%					7.75%
Maturity date, year and month	2027-10					2027-10
Senior Notes [Member]
Debt Instrument [Line Items]
Repayments of long-term debt			$ 700
Over LIBOR [Member] \| Senior Notes [Member]
Debt Instrument [Line Items]
Increase in basis spread			1.75%