Aggregate notional amount specified by the derivative(s). Expressed as an absolute value.

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Article 12

-Section 13

-Sentence Column B

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Accumulated change in equity from transactions and other events and circumstances from non-owner sources, net of tax effect, at period end. Excludes Net Income (Loss), and accumulated changes in equity from transactions resulting from investments by owners and distributions to owners. Includes foreign currency translation items, certain pension adjustments, unrealized gains and losses on certain investments in debt and equity securities, other than temporary impairment (OTTI) losses related to factors other than credit losses on available-for-sale and held-to-maturity debt securities that an entity does not intend to sell and it is not more likely than not that the entity will be required to sell before recovery of the amortized cost basis, as well as changes in the fair value of derivatives related to the effective portion of a designated cash flow hedge.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 11

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e637-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14

-URI http://asc.fasb.org/extlink&oid=36458714&loc=d3e681-108580

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 220

-SubTopic 10

-Section 45

-Paragraph 14A

-URI http://asc.fasb.org/extlink&oid=36458714&loc=SL7669686-108580

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

-Paragraph 31

-Article 5

Reference 5: http://www.xbrl.org/2003/role/presentationRef

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 04

-Article 3

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- Definition

Average fixed interest rate related to the group of interest rate derivatives.

+ References

No definition available.

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- Definition

Number of interest rate derivative instruments held by the entity at the reporting date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1B

-URI http://asc.fasb.org/extlink&oid=35706170&loc=SL5580258-113959

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-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 1A

-Subparagraph (d)

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Derivatives and Risk Management Activities (Details 2) (USD $) In Millions, unless otherwise specified	Mar. 31, 2015	Dec. 31, 2014	Mar. 31, 2014	Dec. 31, 2013
Interest Rate Risk Hedging
Net deferred gains/(losses) from interest rate risk hedging included in AOCI	$ (843)	$ (467)	$ (233)	$ (97)
Interest Rate Derivatives
Interest Rate Risk Hedging
Net deferred gains/(losses) from interest rate risk hedging included in AOCI	(234)
10 forward starting interest rate swaps (30-year) \| Cash flow hedge
Interest Rate Risk Hedging
Number of interest rate derivatives (in contracts)	10
Notional amount of derivatives	250
Rate of fixed interest to be received on interest rate swap (as a percent)	3.60%
8 forward starting interest rate swaps (30-year), one \| Cash flow hedge
Interest Rate Risk Hedging
Number of interest rate derivatives (in contracts)	8
Notional amount of derivatives	200
Rate of fixed interest to be received on interest rate swap (as a percent)	3.06%
8 forward starting interest rate swaps (30-year), two \| Cash flow hedge
Interest Rate Risk Hedging
Number of interest rate derivatives (in contracts)	8
Notional amount of derivatives	200
Rate of fixed interest to be received on interest rate swap (as a percent)	3.14%
8 forward starting interest rate swaps (30-year), three \| Cash flow hedge
Interest Rate Risk Hedging
Number of interest rate derivatives (in contracts)	8
Notional amount of derivatives	200
Rate of fixed interest to be received on interest rate swap (as a percent)	3.20%
8 forward starting interest rate swaps (30-year), four \| Cash flow hedge
Interest Rate Risk Hedging
Number of interest rate derivatives (in contracts)	8
Notional amount of derivatives	$ 200
Rate of fixed interest to be received on interest rate swap (as a percent)	2.83%