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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Face (par) amount of debt instrument at time of issuance.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 835

-SubTopic 30

-Section 55

-Paragraph 8

-URI http://asc.fasb.org/extlink&oid=34725769&loc=d3e28878-108400

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-Topic 835

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-Section 45

-Paragraph 2

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

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-Name Accounting Standards Codification

-Topic 210

-SubTopic 10

-Section S99

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

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-Name Accounting Standards Codification

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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.

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Total debt and equity financial instruments including: (1) securities held-to-maturity and (2) securities available-for-sale that will be held for the long-term.

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-Name Accounting Standards Codification

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-Section 45

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Fair Value of Financial Instruments #2 (Unaudited) (Details) - USD ($) $ in Millions	1 Months Ended
	Feb. 28, 2015	Jun. 30, 2015	Dec. 31, 2014
Investments in Marketable Securities [Abstract]
Marketable Securities, Noncurrent		$ 326	$ 336
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative, Notional Amount		139	146
Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Face Amount	$ 600
Thirty Year Term [Member] \| Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Interest Rate, Stated Percentage	3.85%
Thirty Year Term [Member] \| April 45 Maturity [Domain] \| Senior Notes [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Debt Instrument, Maturity Date	Apr. 15, 2045
Cash Flow Hedging [Member]
Derivative Instruments and Hedging Activities Disclosure [Abstract]
Derivative, Notional Amount		$ 18	$ 34