Other Expenses (Details Textuals) (USD $) In Millions, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Other Expenses [Abstract]
Business acquisition integration related expenses	$ 305	$ 362	$ 176

Costs incurred to effect a business combination which have been expensed during the period. Such costs could include business integration costs, systems integration and conversion costs, and severance and other employee-related costs.

No definition available.

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