Invested Assets (Tables)

9 Months Ended

Sep. 30, 2011

Invested Assets [Abstract]

Amortized cost and fair value of fixed maturities and equity securities

	September 30, 2011
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Appreciation		Depreciation		Value
	(in millions)
Fixed maturities
Tax exempt	$	18,879	$	1,297	$	42	$	20,134
Taxable
U.S. Government and government agency and authority obligations		812		50		2		860
Corporate bonds		6,420		449		31		6,838
Foreign government and government agency obligations		6,293		372		6		6,659
Residential mortgage-backed securities		937		47		5		979
Commercial mortgage-backed securities		1,875		62		2		1,935
		16,337		980		46		17,271
Total fixed maturities	$	35,216	$	2,277	$	88	$	37,405
Equity securities	$	1,271	$	232	$	137	$	1,366

	December 31, 2010
			Gross		Gross
	Amortized		Unrealized		Unrealized		Fair
	Cost		Appreciation		Depreciation		Value
	(in millions)
Fixed maturities
Tax exempt	$	19,072	$	824	$	122	$	19,774
Taxable
U.S. Government and government agency and authority obligations		807		31		9		829
Corporate bonds		6,258		411		21		6,648
Foreign government and government agency obligations		5,943		231		13		6,161
Residential mortgage-backed securities		1,293		63		6		1,350
Commercial mortgage-backed securities		1,688		70		1		1,757
		15,989		806		50		16,745
Total fixed maturities	$	35,061	$	1,630	$	172	$	36,519
Equity securities	$	1,285	$	340	$	75	$	1,550

Amortized cost and fair value of fixed maturities by contractual maturity

	Amortized		Fair
	Cost		Value
	(in millions)
Due in one year or less	$	2,069	$	2,101
Due after one year through five years		11,635		12,274
Due after five years through ten years		11,595		12,626
Due after ten years		7,105		7,490
		32,404		34,491
Residential mortgage-backed securities		937		979
Commercial mortgage-backed securities		1,875		1,935
	$	35,216	$	37,405

Components of unrealized appreciation or depreciation of investments

	September 30		December 31
	2011		2010
	(in millions)
Fixed maturities
Gross unrealized appreciation	$	2,277	$	1,630
Gross unrealized depreciation		88		172
		2,189		1,458
Equity securities
Gross unrealized appreciation		232		340
Gross unrealized depreciation		137		75
		95		265
		2,284		1,723
Deferred income tax liability		799		603
	$	1,485	$	1,120

Fair value and gross unrealized depreciation of investments in an unrealized loss position

	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Depreciation		Value		Depreciation		Value		Depreciation
	(in millions)
Fixed maturities
Tax exempt	$	292	$	3	$	270	$	39	$	562	$	42
Taxable
U.S. Government and government agency and authority obligations		62		1		49		1		111		2
Corporate bonds		753		23		176		8		929		31
Foreign government and government agency obligations		486		5		43		1		529		6
Residential mortgage- backed securities		69		1		21		4		90		5
Commercial mortgage- backed securities		73		1		2		1		75		2
		1,443		31		291		15		1,734		46
Total fixed maturities		1,735		34		561		54		2,296		88
Equity securities		322		72		160		65		482		137
	$	2,057	$	106	$	721	$	119	$	2,778	$	225

	Less Than 12 Months				12 Months or More				Total
			Gross				Gross				Gross
	Fair		Unrealized		Fair		Unrealized		Fair		Unrealized
	Value		Depreciation		Value		Depreciation		Value		Depreciation
	(in millions)
Fixed maturities
Tax exempt	$	2,498	$	79	$	284	$	43	$	2,782	$	122
Taxable
U.S. Government and government agency and authority obligations		111		3		45		6		156		9
Corporate bonds		474		12		166		9		640		21
Foreign government and government agency obligations		990		12		27		1		1,017		13
Residential mortgage- backed securities		9		1		41		5		50		6
Commercial mortgage- backed securities		38		1		—		—		38		1
		1,622		29		279		21		1,901		50
Total fixed maturities		4,120		108		563		64		4,683		172
Equity securities		69		14		299		61		368		75
	$	4,189	$	122	$	862	$	125	$	5,051	$	247

Change in unrealized appreciation or depreciation of investments carried at fair value

	Periods Ended September 30
	Third Quarter					Nine Months
	2011			2010		2011			2010
	(in millions)
Change in unrealized appreciation of fixed maturities	$	478		$	589	$	731		$	1,031
Change in unrealized appreciation of equity securities		(276	)		118		(170	)		(67	)
		202			707		561			964
Deferred income tax		70			247		196			337
	$	132		$	460	$	365		$	627

Realized investment gains and losses

	Periods Ended September 30
	Third Quarter						Nine Months
	2011			2010			2011			2010
	(in millions)
Fixed maturities
Gross realized gains	$	25		$	14		$	48		$	71
Gross realized losses		(10	)		(6	)		(25	)		(17	)
Other-than-temporary impairment losses		(1	)		—			(1	)		(3	)
		14			8			22			51
Equity securities
Gross realized gains		16			18			45			30
Gross realized losses		—			—			(1	)		(1	)
Other-than-temporary impairment losses		(6	)		—			(22	)		(6	)
		10			18			22			23
Other invested assets		47			28			256			197
	$	71		$	54		$	300		$	271