Segments of Operations (Details Textual) (USD $) In Millions, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2012	Jun. 30, 2011	Jun. 30, 2012	Jun. 30, 2011
Segments of Operations (Textual) [Abstract]
Earnings (losses) of managed investment entities attributable to noncontrolling interests	$ (18)	$ (20)	$ (46)	$ (55)
Property and Casualty Insurance [Member]
Segments of Operations (Textual) [Abstract]
Special charges to increase asbestos and environmental reserves		50		50
Other Segment [Member]
Segments of Operations (Textual) [Abstract]
Earnings (losses) of managed investment entities attributable to noncontrolling interests	$ (18)	$ (20)	$ (46)	$ (55)