Fair Value Measurements (tables)

9 Months Ended

Sep. 30, 2012

Fair Value Measurements disclosure

Level within the fair value hierarchy at which the Company's financial assets and financial liabilities are measured [Table Text Block]

(at September 30, 2012, in millions)	Total		Level 1		Level 2		Level 3
Invested assets:
Fixed maturities
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities	$	2,171	$	2,154	$	17	$	—
Obligations of states, municipalities and political subdivisions	39,252		—		39,224		28
Debt securities issued by foreign governments	2,366		—		2,366		—
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities	3,154		—		3,149		5
All other corporate bonds	18,897		8		18,689		200
Redeemable preferred stock	33		32		1		—
Total fixed maturities	65,873		2,194		63,446		233
Equity securities
Common stock	496		496		—		—
Non-redeemable preferred stock	133		95		38		—
Total equity securities	629		591		38		—
Other investments	89		42		—		47
Total	$	66,591	$	2,827	$	63,484	$	280

(at December 31, 2011, in millions)	Total		Level 1		Level 2		Level 3
Invested assets:
Fixed maturities
U.S. Treasury securities and obligations of U.S. government and government agencies and authorities	$	2,497	$	2,465	$	32	$	—
Obligations of states, municipalities and political subdivisions	39,022		—		39,002		20
Debt securities issued by foreign governments	2,318		—		2,318		—
Mortgage-backed securities, collateralized mortgage obligations and pass-through securities	3,515		—		3,514		1
All other corporate bonds	16,850		—		16,621		229
Redeemable preferred stock	30		29		1		—
Total fixed maturities	64,232		2,494		61,488		250
Equity securities
Common stock	428		428		—		—
Non-redeemable preferred stock	131		96		35		—
Total equity securities	559		524		35		—
Other investments	86		42		—		44
Total	$	64,877	$	3,060	$	61,523	$	294

Changes in the Level 3 fair value category [Table Text Block]

Three Months Ended September 30, 2012 (in millions)	FixedMaturities			OtherInvestments		Total
Balance at June 30, 2012	$	254		$	44	$	298
Total realized and unrealized investment gains (losses):
Reported in realized investment gains (losses) (1)	1			—		1
Reported in increases (decreases) in other comprehensive income	1			2		3
Purchases, sales and settlements/maturities:
Purchases	13			1		14
Sales	—			—		—
Settlements/maturities	(28		)	—		(28		)
Gross transfers into Level 3	3			—		3
Gross transfers out of Level 3	(11		)	—		(11		)
Balance at September 30, 2012	$	233		$	47	$	280
Amount of total realized investment gains (losses) for the period included in the consolidated statement of income attributable to changes in the fair value of assets still held at the reporting date	$	—		$	—	$	—

(1)Includes impairments on investments held at the end of the period.

Nine Months Ended September 30, 2012 (in millions)	FixedMaturities			OtherInvestments			Total
Balance at December 31, 2011	$	250		$	44		$	294
Total realized and unrealized investment gains (losses):
Reported in realized investment gains (losses) (1)	3			(1		)	2
Reported in increases (decreases) in other comprehensive income	5			3			8
Purchases, sales and settlements/maturities:
Purchases	63			1			64
Sales	—			—			—
Settlements/maturities	(73		)	—			(73		)
Gross transfers into Level 3	9			—			9
Gross transfers out of Level 3	(24		)	—			(24		)
Balance at September 30, 2012	$	233		$	47		$	280
Amount of total realized investment gains (losses) for the period included in the consolidated statement of income attributable to changes in the fair value of assets still held at the reporting date	$	—		$	—		$	—

(1)Includes impairments on investments held at the end of the period.

Twelve Months Ended December 31, 2011 (in millions)	FixedMaturities			OtherInvestments			Total
Balance at December 31, 2010	$	230		$	57		$	287
Total realized and unrealized investment gains (losses):
Reported in realized investment gains (losses) (1)	1			38			39
Reported in increases (decreases) in other comprehensive income	—			(9		)	(9		)
Purchases, sales and settlements/maturities:
Purchases	154			5			159
Sales	(15		)	(47		)	(62		)
Settlements/maturities	(43		)	—			(43		)
Gross transfers into Level 3	19			—			19
Gross transfers out of Level 3 (2)	(96		)	—			(96		)
Balance at December 31, 2011	$	250		$	44		$	294
Amount of total realized investment gains (losses) for the period included in the consolidated statement of income attributable to changes in the fair value of assets still held at the reporting date	$	—		$	—		$	—

(1)      Includes impairments on investments held at the end of the period.

(2)   During the year ended December 31, 2011, approximately $81 million of municipal fixed maturity securities were valued using observable market data which resulted in a transfer out of Level 3 into Level 2.  In prior periods, these securities were valued internally using unobservable inputs.

Carrying value and fair value of financial instruments disclosed, but not carried, at fair value and the level within the fair value hierarchy at which such financial instruments are measured on a recurring basis [Table Text Block]

(at September 30, 2012, in millions)	Carrying Value		Fair Value		Level 1		Level 2		Level 3
Financial assets:
Short-term securities	$	3,641	$	3,641	$	1,518	$	2,039	$	84
Financial liabilities:
Debt	$	6,250	$	7,797	$	—	$	7,442	$	355
Commercial paper	100		100		—		100		—

(at December 31, 2011, in millions)	Carrying Value		Fair Value		Level 1		Level 2		Level 3
Financial assets:
Short-term securities	$	3,594	$	3,594	$	2,472	$	1,029	$	93
Financial liabilities:
Debt	$	6,505	$	7,609	$	—	$	7,057	$	552
Commercial paper	100		100		—		100		—