Investments (Details 1) (USD $) In Millions, unless otherwise specified	Sep. 30, 2011	Dec. 31, 2010
U.S. Government and government agencies [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	$ 0	$ (1)
Fair Value - Less than twelve months	31	86
Fair Value as % of Cost - Less than twelve months	100.00%	99.00%
Unrealized Loss - Twelve months or more	0	0
Fair Value - Twelve months or more	0	0
Fair Value as % of Cost - Twelve months or more	0.00%	0.00%
States, municipalities and political subdivisions [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(2)	(38)
Fair Value - Less than twelve months	162	1,180
Fair Value as % of Cost - Less than twelve months	99.00%	97.00%
Unrealized Loss - Twelve months or more	(2)	(3)
Fair Value - Twelve months or more	48	40
Fair Value as % of Cost - Twelve months or more	96.00%	93.00%
Foreign government [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	0	0
Fair Value - Less than twelve months	0	37
Fair Value as % of Cost - Less than twelve months	0.00%	99.00%
Unrealized Loss - Twelve months or more	0	0
Fair Value - Twelve months or more	0	0
Fair Value as % of Cost - Twelve months or more	0.00%	0.00%
Residential Mortgage Backed Securities [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(40)	(11)
Fair Value - Less than twelve months	942	412
Fair Value as % of Cost - Less than twelve months	96.00%	97.00%
Unrealized Loss - Twelve months or more	(105)	(117)
Fair Value - Twelve months or more	444	551
Fair Value as % of Cost - Twelve months or more	81.00%	82.00%
Commercial Mortgage Backed Securities [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(11)	(2)
Fair Value - Less than twelve months	285	83
Fair Value as % of Cost - Less than twelve months	96.00%	98.00%
Unrealized Loss - Twelve months or more	0	0
Fair Value - Twelve months or more	7	15
Fair Value as % of Cost - Twelve months or more	100.00%	97.00%
All Other Corporate [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(48)	(24)
Fair Value - Less than twelve months	1,146	1,020
Fair Value as % of Cost - Less than twelve months	96.00%	98.00%
Unrealized Loss - Twelve months or more	(14)	(20)
Fair Value - Twelve months or more	81	275
Fair Value as % of Cost - Twelve months or more	85.00%	93.00%
Fixed Maturity Securities [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(101)	(76)
Fair Value - Less than twelve months	2,566	2,818
Fair Value as % of Cost - Less than twelve months	96.00%	97.00%
Unrealized Loss - Twelve months or more	(121)	(140)
Fair Value - Twelve months or more	580	881
Fair Value as % of Cost - Twelve months or more	83.00%	86.00%
Common Stocks [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(39)	0
Fair Value - Less than twelve months	260	21
Fair Value as % of Cost - Less than twelve months	87.00%	99.00%
Unrealized Loss - Twelve months or more	0	(1)
Fair Value - Twelve months or more	0	4
Fair Value as % of Cost - Twelve months or more	0.00%	88.00%
Perpetual preferred stocks [Member]
Available for sale securities in a continuous unrealized loss position
Unrealized Loss - Less than twelve months	(3)	0
Fair Value - Less than twelve months	43	22
Fair Value as % of Cost - Less than twelve months	93.00%	98.00%
Unrealized Loss - Twelve months or more	(6)	(5)
Fair Value - Twelve months or more	$ 34	$ 37
Fair Value as % of Cost - Twelve months or more	85.00%	88.00%

Available for sale securities continuous unrealized loss position less than twelve months fair value as percentage of cost

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This item represents the excess of amortized cost basis over fair value of securities that have been in a loss position for less than twelve months for those securities which are categorized neither as held-to-maturity nor trading securities.

+ References

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+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher FASB

-Name FASB Staff Position (FSP)

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