Investments (Tables)

12 Months Ended

Dec. 31, 2011

Fixed maturities, short-term investments and equities

						Gross		Gross
						Unrealized		Unrealized		Fair
December 31, 2011			Cost⁽¹⁾		Gains		Losses		Value

Fixed maturities
	U.S. government and government sponsored enterprises		$	1,084,533	$	31,283	$	(39)	$	1,115,777
	U.S. states, territories and municipalities			117,528		6,169		(13)		123,684
	Non-U.S. sovereign government, supranational and
		government related		2,807,363		158,900		(2,172)		2,964,091
	Corporate			5,461,478		319,090		(33,571)		5,746,997
	Asset-backed securities			626,508		11,558		(4,267)		633,799
	Residential mortgage-backed securities			3,224,850		94,781		(36,730)		3,282,901
	Other mortgage-backed securities			72,144		2,833		(397)		74,580

Total fixed maturities				13,394,404		624,614		(77,189)		13,941,829
Short-term investments				42,563		22		(14)		42,571
Equities				917,613		99,152		(72,074)		944,691

Total			$	14,354,580	$	723,788	$	(149,277)	$	14,929,091

						Gross		Gross
						Unrealized		Unrealized		Fair
December 31, 2010			Cost⁽¹⁾		Gains		Losses		Value
Fixed maturities
	U.S. government and government sponsored enterprises		$	895,862	$	15,584	$	(5,414)	$	906,032
	U.S. states, territories and municipalities			66,548		271		(127)		66,692
	Non-U.S. sovereign government, supranational and
		government related		2,743,922		82,984		(7,713)		2,819,193
	Corporate			5,876,392		286,463		(19,008)		6,143,847
	Asset-backed securities			554,326		11,707		(9,376)		556,657
	Residential mortgage-backed securities			2,227,938		92,534		(14,947)		2,305,525
	Other mortgage-backed securities			29,809		1,787		(5,153)		26,443

Total fixed maturities				12,394,797		491,330		(61,738)		12,824,389
Short-term investments				49,132		283		(18)		49,397
Equities				942,745		146,700		(17,769)		1,071,676

Total			$	13,386,674	$	638,313	$	(79,525)	$	13,945,462
_______________

Maturity distribution of fixed maturities and short-term investments

		Cost		Fair Value

One year or less	$	566,515	$	570,829
More than one year through five years		4,792,769		4,923,116
More than five years through ten years		3,471,876		3,713,242
More than ten years		682,305		785,933

Subtotal		9,513,465		9,993,120
Mortgage/asset-backed securities		3,923,502		3,991,280

Total	$	13,436,967	$	13,984,400

Net realized and unrealized investment gains (losses)

			2011		2010		2009

Net realized investment gains on fixed maturities and short-term investments		$	157,207	$	173,426	$	105,249
Net realized investment gains (losses) on equities			90,866		44,736		(45,258)
Net realized losses on other invested assets			(176,295)		(68,568)		(35,426)
Change in net unrealized (losses) gains on other invested assets			(46,278)		3,742		58,196
Change in net unrealized investment gains on fixed maturities and
	short-term investments		128,224		142,634		322,944
Change in net unrealized investment (losses) gains on equities			(101,860)		64,825		185,925
Net other realized and unrealized investment gains			3,617		13,335		1,777
Net realized and unrealized investment gains (losses)
	on funds held – directly managed		11,211		27,352		(1,700)

Total net realized and unrealized investment gains		$	66,692	$	401,482	$	591,707

Net investment income

		2011		2010		2009

Fixed maturities	$	561,576	$	580,258	$	559,330
Short-term investments, cash and cash equivalents		3,843		8,541		11,799
Equities		19,815		20,794		13,861
Funds held and other		49,502		52,794		32,793
Funds held – directly managed		37,919		51,775		17,766
Investment expenses		(43,507)		(41,380)		(39,478)

Net investment income	$	629,148	$	672,782	$	596,071

Net payable/receivable for securities sold/purchased

		2011		2010

Receivable for securities sold	$	71,477	$	16,669
Payable for securities purchased		(86,557)		(23,802)

Net payable for securities purchased/sold	$	(15,080)	$	(7,133)

- Definition

Tabular disclosure of the realized and unrealized gains and losses reported in the statement of income which have resulted from the sale and holding of marketable securities, respectively, as well as the sale or disposal of cost method investments. Such amounts would include realized gains and losses on the sale or disposal of trading, available-for-sale, and held-to-maturity securities, unrealized gains and losses on trading securities, unrealized gains and losses on available-for-sale and held-to-maturity securities transferred to the trading securities category, realized gains and losses on the sale or disposal of cost method investments, and losses recognized for other than temporary impairments (OTTI) of such investments.

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- Definition

Tabular disclosure of investment income derived from investments in debt and equity securities consisting of interest income earned from investments in debt securities and on cash and cash equivalents, dividend income from investments in equity securities, and income or expense derived from the amortization of investment related discounts or premiums, respectively. This item does not include realized or unrealized gains or losses on the sale or holding of investments in debt and equity securities required to be included in earnings for the period or for other than temporary losses related to investments in debt and equity securities which are included in realized losses in the period recognized.

+ References+ Details

- Definition

Tabular disclosure of trading securities (and certain trading assets) which consist of all investments in certain debt and equity securities (and other assets) that are bought and held principally for the purpose of selling them in the near term (thus held for only a short period of time) or for which an entity has elected the fair value option. Trading generally reflects active and frequent buying and selling, and trading securities are generally used with the objective of generating profits on short-term differences in price, but this category of investments may also include items which are not intended to be sold in the near term or for which the fair value option has been elected.

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