Invested Assets (Tables)

9 Months Ended

Sep. 30, 2013

Text Block [Abstract]

Amortized Cost and Fair Value of Fixed Maturities and Equity Securities

(a) The amortized cost and fair value of fixed maturities and equity securities were as follows:

	September 30, 2013
	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation		Fair Value
	(in millions)
Fixed maturities
Tax exempt	$	18,210	$	905	$	164	$	18,951
Taxable
U.S. government and government agency and authority obligations		790		35		7		818
Corporate bonds		8,838		399		77		9,160
Foreign government and government agency obligations		6,773		238		24		6,987
Residential mortgage-backed securities		302		23		1		324
Commercial mortgage-backed securities		1,333		39		2		1,370
		18,036		734		111		18,659
Total fixed maturities	$	36,246	$	1,639	$	275	$	37,610
Equity securities	$	1,163	$	665	$	7	$	1,821

	December 31, 2012
	Amortized Cost		Gross Unrealized Appreciation		Gross Unrealized Depreciation		Fair Value
	(in millions)
Fixed maturities
Tax exempt	$	18,410	$	1,522	$	19	$	19,913
Taxable
U.S. government and government agency and authority obligations		973		66		—		1,039
Corporate bonds		7,331		609		3		7,937
Foreign government and government agency obligations		6,614		395		1		7,008
Residential mortgage-backed securities		421		36		2		455
Commercial mortgage-backed securities		1,649		76		1		1,724
		16,988		1,182		7		18,163
Total fixed maturities	$	35,398	$	2,704	$	26	$	38,076
Equity securities	$	1,244	$	453	$	34	$	1,663

Fair Value and Amortized Cost of Fixed Maturities by Contractual Maturity

The fair value and amortized cost of fixed maturities at September 30, 2013 by contractual maturity were as follows:

	Fair Value		Amortized Cost
	(in millions)
Due in one year or less	$	2,180	$	2,149
Due after one year through five years		14,165		13,581
Due after five years through ten years		11,717		11,148
Due after ten years		7,854		7,733
		35,916		34,611
Residential mortgage-backed securities		324		302
Commercial mortgage-backed securities		1,370		1,333
	$	37,610	$	36,246

Components of Unrealized Appreciation or Depreciation of Investments

(b) The components of unrealized appreciation or depreciation, including unrealized other-than-temporary impairment losses, of investments carried at fair value were as follows:

	September 30 2013		December 31 2012
	(in millions)
Fixed maturities
Gross unrealized appreciation	$	1,639	$	2,704
Gross unrealized depreciation		275		26
		1,364		2,678
Equity securities
Gross unrealized appreciation		665		453
Gross unrealized depreciation		7		34
		658		419
		2,022		3,097
Deferred income tax liability		708		1,084
	$	1,314	$	2,013

Fair Value and Gross Unrealized Depreciation of Investments in Unrealized Loss Position

The following table summarizes, for all investment securities in an unrealized loss position at September 30, 2013, the aggregate fair value and gross unrealized depreciation, including unrealized other-than-temporary impairment losses, by investment category and length of time that individual securities have continuously been in an unrealized loss position.

	Less Than 12 Months				12 Months or More				Total
	Fair Value		Gross Unrealized Depreciation		Fair Value		Gross Unrealized Depreciation		Fair Value		Gross Unrealized Depreciation
	(in millions)
Fixed maturities
Tax exempt	$	2,900	$	145	$	128	$	19	$	3,028	$	164
Taxable
U.S. government and government agency and authority obligations		139		3		34		4		173		7
Corporate bonds		2,512		75		42		2		2,554		77
Foreign government and government agency obligations		1,519		22		36		2		1,555		24
Residential mortgage-backed securities		3		—		15		1		18		1
Commercial mortgage-backed securities		94		2		16		—		110		2
		4,267		102		143		9		4,410		111
Total fixed maturities		7,167		247		271		28		7,438		275
Equity securities		45		4		11		3		56		7
	$	7,212	$	251	$	282	$	31	$	7,494	$	282

The following table summarizes, for all investment securities in an unrealized loss position at December 31, 2012, the aggregate fair value and gross unrealized depreciation, including unrealized other-than-temporary impairment losses, by investment category and length of time that individual securities have continuously been in an unrealized loss position.

	Less Than 12 Months				12 Months or More				Total
	Fair Value		Gross Unrealized Depreciation		Fair Value		Gross Unrealized Depreciation		Fair Value		Gross Unrealized Depreciation
	(in millions)
Fixed maturities
Tax exempt	$	344	$	6	$	104	$	13	$	448	$	19
Taxable
U.S. government and government agency and authority obligations		28		—		20		—		48		—
Corporate bonds		289		2		14		1		303		3
Foreign government and government agency obligations		429		1		13		—		442		1
Residential mortgage-backed securities		1		—		19		2		20		2
Commercial mortgage-backed securities		105		1		3		—		108		1
		852		4		69		3		921		7
Total fixed maturities		1,196		10		173		16		1,369		26
Equity securities		182		21		63		13		245		34
	$	1,378	$	31	$	236	$	29	$	1,614	$	60

Change in Unrealized Appreciation or Depreciation of Investments Carried at Fair Value

The change in unrealized appreciation or depreciation of investments carried at fair value, including the change in unrealized other-than-temporary impairment losses, was as follows:

	Periods Ended September 30
	Third Quarter					Nine Months
	2013			2012		2013			2012
	(in millions)
Change in unrealized appreciation of fixed maturities	$	(99	)	$	295	$	(1,314	)	$	411
Change in unrealized appreciation of equity securities		94			57		239			131
		(5	)		352		(1,075	)		542
Deferred income tax (credit)		(2	)		123		(376	)		190
	$	(3	)	$	229	$	(699	)	$	352

Realized Investment Gains and Losses

(c) Realized investment gains and losses were as follows:

	Periods Ended September 30
	Third Quarter						Nine Months
	2013			2012			2013			2012
	(in millions)
Fixed maturities
Gross realized gains	$	17		$	35		$	44		$	97
Gross realized losses		(22	)		(8	)		(32	)		(18	)
Other-than-temporary impairment losses		(2	)		(2	)		(2	)		(4	)
		(7	)		25			10			75
Equity securities
Gross realized gains		5			25			179			50
Gross realized losses		(1	)		—			(1	)		—
Other-than-temporary impairment losses		(2	)		(5	)		(9	)		(40	)
		2			20			169			10
Other invested assets		23			(45	)		156			18
	$	18		$	—		$	335		$	103