Fair Value (Fair Value Measurements - Recurring Fair Value Inputs) (Details) (USD $) In Millions, unless otherwise specified					12 Months Ended
Dec. 31, 2013 Fair Value, Measurements, Recurring [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member]	Dec. 31, 2013 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2012 Fair Value, Measurements, Recurring [Member] Fair Value, Inputs, Level 3 [Member]	Dec. 31, 2013 Retained Interest [Member] Discounted cash flow [Member] Minimum [Member]	Dec. 31, 2013 Retained Interest [Member] Discounted cash flow [Member] Maximum [Member]
Fair value inputs, Quantitative Information [Line Items]
Fair Value Inputs, Discount Rate					5.30%	5.50%
Retained Interest, Fair Value Disclosure	$ 100	$ 154	$ 100	$ 154
Fair Value Inputs, Commercial Paper Rate					0.00%	0.10%

Interest rate used to find the present value of an amount to be paid or received in the future as an input to measure fair value. For example, but not limited to, weighted average cost of capital (WACC), cost of capital, cost of equity and cost of debt.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 820

-SubTopic 10

-Section 50

-Paragraph 2

-Subparagraph (bbb)

-URI http://asc.fasb.org/extlink&oid=25499696&loc=d3e19207-110258

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