Aggregate net gain and losses (whether realized or unrealized) on all derivative instruments held for trading purposes whether or not settled physically.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 45

-Paragraph 9

-URI http://asc.fasb.org/extlink&oid=6945355&loc=d3e41322-113958

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 815

-SubTopic 10

-Section 50

-Paragraph 4F

-URI http://asc.fasb.org/extlink&oid=7476318&loc=SL5624186-113959

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 02-3

-Paragraph 8

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

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Namespace Prefix:	us-gaap_
Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	duration

Derivative Financial Instruments (Summary of recognized gains (losses) related to derivative financial instruments) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Recognized Gains (Losses)
Derivative instruments not designated as hedging instruments, gain (loss), net	$ (2)		$ (1)
Gain (loss) on derivative instruments, net, pretax	(2)		(2)
Currency forwards [Member]
Recognized Gains (Losses)
Derivative instruments not designated as hedging instruments, gain (loss), net	(2)
Credit default swap - purchased protection [Member]
Recognized Gains (Losses)
Derivative instruments not designated as hedging instruments, gain (loss), net			(1)
Futures sold, not yet purchased [Member]
Recognized Gains (Losses)
Gain (loss) on derivative instruments held for trading purposes, net			$ (1)