Investments (Details 50) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2011	Dec. 31, 2010	Dec. 31, 2009
Net Income from Investment in leveraged leases
Net Investment income from investment in leveraged leases	$ 125	$ 123	$ 114
Less: Income tax expense on leveraged leases net investment income	(44)	(43)	(40)
Net investment income after income tax from investment in leveraged leases	$ 81	$ 80	$ 74

The tax effect from the current year income from arrangements meeting the criteria for classification as a leveraged lease.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

-Number 13

-Paragraph 47

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009.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.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 840

-SubTopic 30

-Section 45

-Paragraph 5

-URI http://asc.fasb.org/extlink&oid=6792436&loc=d3e45152-112736

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