Fair Value Disclosures - Narrative (Details) (Level 3 [Member], USD $) In Billions, unless otherwise specified	Jun. 30, 2014	Dec. 31, 2013
Level 3 [Member]
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items]
Assets and Liabilities, Fair Value Disclosure	$ 5.2	$ 6.8
Fair Value, Assets and Liabilities Fair Value as Percent of Total Assets	35.00%	51.00%
Fair Value, Assets and Liabilities, Fair Value as Percent of Total Financial Instruments Measured at Fair Value	56.00%	73.00%

Fair Value, Assets and Liabilities, Fair Value as Percent of Total Financial Instruments Measured at Fair Value

No definition available.

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Period Type:	instant