Other Assets (Parenthetical) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2012	Dec. 31, 2011
Other Assets [Line Items]
Deferred Tax Liabilities, Net	$ 5,871	$ 7,052
Valuation allowances	200	122
Unamortized fees related to special programs	0	329
Adjustment to deferred acquisition costs in run off insurance operations	764	810
Unrealized Loss On Cost Method Investments In Continuous Loss Position Insignificant Amount	an insignificant amount
Continuous Loss Position Less Than Twelve Months [Member]
Other Assets [Line Items]
Fair value on cost method investments in a continuous loss position	142	425
Unrealized loss on cost method investments in a continuous loss position	37	61
Continuous Loss Position More Than Twelve Months [Member]
Other Assets [Line Items]
Fair value on cost method investments in a continuous loss position	2	65
Unrealized loss on cost method investments in a continuous loss position		$ 3
Americas [Member]
Other Assets [Line Items]
Category of real estate investments	45.00%
Europe [Member]
Other Assets [Line Items]
Category of real estate investments	28.00%
Asia [Member]
Other Assets [Line Items]
Category of real estate investments	27.00%
Office Building [Member]
Other Assets [Line Items]
Category of real estate investments	48.00%
Apartment Building [Member]
Other Assets [Line Items]
Category of real estate investments	14.00%
Industrial Properties [Member]
Other Assets [Line Items]
Category of real estate investments	8.00%
Retail Facilities [Member]
Other Assets [Line Items]
Category of real estate investments	9.00%
Franchise Properties [Member]
Other Assets [Line Items]
Category of real estate investments	9.00%
Other Properties [Member]
Other Assets [Line Items]
Category of real estate investments	12.00%