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

No definition available.

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- Definition

Debt Instrument, Incremental Decrease in Basis Spread on Variable Rate Resulting from Upgrades

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No definition available.

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- Definition

Debt Instrument, Incremental Increase in Basis Spread on Variable Rate Resulting from Downgrades

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No definition available.

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- Definition

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

+ References

No definition available.

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- Definition

Debt Instrument, Percentage of Face Amount, Sold to Public

+ References

No definition available.

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- Definition

Purchase Of Note Principal

+ References

No definition available.

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- Definition

Short-Term financing which is expected to be paid back relatively quickly, such as by a subsequent longer-term loan. Also called swing loan or bridge financing.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 942
-SubTopic 210
-Section S99
-Paragraph 1
-Subparagraph (SX 210.9-03(13))
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- Definition

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
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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

Period of time between issuance and maturity of debt instrument, in PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

+ References

No definition available.

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- Definition

Amount, after accumulated amortization, of debt premium.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 835
-SubTopic 30
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- Definition

Amount, before accumulated amortization, of debt issuance costs. Includes, but is not limited to, legal, accounting, underwriting, printing, and registration costs.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
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-SubTopic 30
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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.

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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

The cash inflow during the period from additional borrowings in aggregate debt. Includes proceeds from short-term and long-term debt.

+ References

No definition available.

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- Definition

Carrying value as of the balance sheet date of Notes with the highest claim on the assets of the issuer in case of bankruptcy or liquidation (with maturities initially due after one year or beyond the operating cycle if longer), excluding current portion. Senior note holders are paid off in full before any payments are made to junior note holders.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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-Subparagraph (SX 210.5-02.22)
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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.

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Debt (Senior Notes - Narrative) (Details) - USD ($) $ in Millions	1 Months Ended			3 Months Ended	9 Months Ended		12 Months Ended
	Jul. 31, 2016	Jan. 31, 2015	Dec. 31, 2014	Sep. 30, 2016	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 2015
Debt Instrument [Line Items]
Net loss on extinguishment of debt				$ (51)	$ (51)
Unamortized debt expense				30	30		$ 24
Long-term Debt [Member]
Debt Instrument [Line Items]
Unamortized debt expense				$ 30	$ 30		24
Senior Notes [Member]
Debt Instrument [Line Items]
Proceeds from issuance of debt		$ 2,200
Purchase of note principal	$ 700
Net loss on extinguishment of debt	(51)
Premium	50
Unamortized debt expense	$ 2
Senior Notes [Member] \| Over LIBOR [Member]
Debt Instrument [Line Items]
Incremental increase in basis points resulting from downgrades					0.25%
Incremental decrease in basis points resulting from upgrades					0.25%
Increase in basis spread	1.75%
Bridge Loan [Member]
Debt Instrument [Line Items]
Bridge loan		$ 4,500	$ 4,500				$ 4,500
Debt instrument, term		364 days	364 days				364 days
Debt issuance costs		$ 47
3.30% Senior Notes due January 2018 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Senior notes		$ 350
Stated interest rate	5.05%	3.30%		3.30%	3.30%		3.30%
Maturity date, year		2018
Percentage of face amount, sold to public		99.949%
Unamortized debt expense							$ 2
4.05% Senior Notes due January 2020 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Senior notes		$ 850
Stated interest rate	5.80%	4.05%		4.05%	4.05%		4.05%
Maturity date, year		2020
Percentage of face amount, sold to public		99.897%
Unamortized debt expense				$ 5	$ 5		$ 5
4.95% Senior Notes due January 2025 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Senior notes		$ 1,000
Stated interest rate	6.70%	4.95%		4.95%	4.95%		4.95%
Maturity date, year		2025
Percentage of face amount, sold to public		99.782%
Unamortized debt expense				$ 7	$ 7		$ 7
Maximum [Member] \| 3.30% Senior Notes due January 2018 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Stated interest rate				5.30%	5.30%
Maximum [Member] \| 4.05% Senior Notes due January 2020 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Stated interest rate				6.05%	6.05%
Maximum [Member] \| 4.95% Senior Notes due January 2025 [Member] \| Long-term Debt [Member]
Debt Instrument [Line Items]
Stated interest rate				6.95%	6.95%