Financing (Senior Notes) (Narrative) (Details) (USD $) In Billions, unless otherwise specified	12 Months Ended
Dec. 31, 2014 D Rate
Debt Disclosure [Abstract]
Aggregate principle of unsecured senior notes	$ 1.4us-gaap_LongTermDebt
Interest rate of notes, minimum	3.80%
Interest rate of notes, maximum	4.875%
Number of days in annual interest calculation period	360
Debt instrument covenant description	Each of the senior notes is subject to certain customary covenants, with which the Company complied as of December 31, 2014.

The number of days in a year used to calculate interest.

No definition available.

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- Definition

States whether the entity was in compliance with the debt covenants throughout the reporting period, and describes facts and circumstances of any compliance failure.

+ References

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 02

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-Subparagraph (g)

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- Definition

Maximum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Minimum contractual interest rate for funds borrowed, under the debt agreement.

+ References

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- Definition

Carrying amount of long-term debt, net of unamortized discount or premium, including current and noncurrent amounts. 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

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-Name Regulation S-X (SX)

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