v2.4.0.8

Investments (Details) (USD $) In Millions, unless otherwise specified	Mar. 31, 2014	Dec. 31, 2013	Mar. 31, 2014 LCH Invetment [Member]	Mar. 31, 2014 Borsa Istanbul Cost Method Investment[Member]	Mar. 31, 2014 Foreign Government Debt Securities [Member]	Dec. 31, 2013 Foreign Government Debt Securities [Member]	Sep. 30, 2013 EMCF [Member]	Mar. 31, 2014 EuroCCP [Member]
Investments, Debt and Securities [Line Items]
Trading securities	$ 192	$ 189			$ 177	$ 167
Equity Method Investment Ownership Percentage							22.00%	25.00%
Available for sale, fair value	5
Equity method investments	29	30
Carrying cost of Investment		$ 65	$ 144	$ 75
Cost Method Investment Ownership Percentage	5.00%		5.00%

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Cost Method Investment in Ownership Percentage

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Amount of investment in debt and equity securities categorized neither as held-to-maturity nor trading.

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Amount, after adjustment, of cost-method investment. Adjustments include, but are not limited to, dividends received in excess of earnings after date of investment that are considered a return of investment and other than temporary impairments.

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The percentage of ownership of common stock or equity participation in the investee accounted for under the equity method of accounting.

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Amount of investments in debt and equity securities and other forms of securities that provide ownership interests classified as trading.

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