Fair Value Measurements (Tables)

12 Months Ended

Dec. 31, 2011

Fair Value, Assets and Liabilities Measured on Recurring Basis [Abstract]

Assets And Liabilities Measured At Fair value, On A Recurring Basis

The following tables present the assets and liabilities measured at fair value on a recurring basis as of December 31, 2011 and 2010 by level:

(Dollars in thousands)	Total		Level 1		Level 2		Level 3
December 31, 2011
Assets:
Fixed maturity securities available for sale:
U.S. government and government agency	$	976,493	$	—	$	976,493	$	—
State and municipal	5,323,070		—		5,323,070		—
Mortgage-backed securities	1,584,587		—		1,584,587		—
Corporate	2,424,424		—		2,356,596		67,828
Foreign	888,354		—		888,354		—
Total fixed maturity securities available for sale	11,196,928		—		11,129,100		67,828
Equity securities available for sale:
Common stocks	319,982		318,423		—		1,559
Preferred stocks	123,457		—		111,154		12,303
Total equity securities available for sale	443,439		318,423		111,154		13,862
Arbitrage trading account	397,312		208,516		187,945		851
Total	$	12,037,679	$	526,939	$	11,428,199	$	82,541
Liabilities:
Securities sold but not yet purchased	$	62,514	$	62,493	$	—	$	21
December 31, 2010
Assets:
Fixed maturity securities available for sale:
U.S. government and government agency	$	1,347,875	$	—	$	1,347,875	$	—
State and municipal	5,461,446		—		5,461,446		—
Mortgage-backed securities	1,411,846		—		1,411,846		—
Corporate	2,119,922		—		2,031,859		88,063
Foreign	752,070		—		752,070		—
Total fixed maturity securities available for sale	11,093,159		—		11,005,096		88,063
Equity securities available for sale:
Common stocks	316,056		204,749		109,748		1,559
Preferred stocks	244,997		—		155,551		89,446
Total equity securities available for sale	561,053		204,749		265,299		91,005
Arbitrage trading account	359,192		162,292		193,713		3,187
Total	$	12,013,404	$	367,041	$	11,464,108	$	182,255
Liabilities:
Securities sold but not yet purchased	$	53,494	$	51,672	$	1,822	$	—

Summarize Changes In Level 3 Assets

The following tables summarize changes in Level 3 assets and liabilities for the years ended December 31, 2011 and 2010:

	Gains (Losses) Included in:
(Dollars in thousands)	Beginning Balance		Earnings			Other Comprehensive Income				Purchases		Sales			Paydowns/Maturities			In		Out			Ending Balance
Year ended December 31, 2011
Assets:
Fixed maturity securities available for sale:
Corporate	$	88,063	$	(454	)	$	(870	)		$	15,271	$	(11,864	)	$	(22,318	)	$	—	$	—		$	67,828
Total	88,063		(454		)	(870		)		15,271		(11,864		)	(22,318		)	—		—			67,828
Equity securities available for sale:
Common stocks	1,559		—			—				—		—			—			—		—			1,559
Preferred stocks	89,446		28,947			(30,865		)		—		(75,225		)	—			—		—			12,303
Total	91,005		28,947			(30,865		)		—		(75,225		)	—			—		—			13,862
Arbitrage trading account	3,187		572			—			—	269		(3,266		)	—			89		—			851
Total	$	182,255	$	29,065		$	(31,735	)		$	15,540	$	(90,355	)	$	(22,318	)	$	89	$	—		$	82,541
Liabilities:
Securities sold but not yet purchased	—		$	40		—				$	67	$	(86	)	—			—		—			$	21
Year ended December 31, 2010
Fixed maturity securities available for sale:
Mortgage-backed securities	$	25,900	$	—		$	—			$	—	$	—		$	—		$	—	$	(25,900	)	$	—
Corporate	90,160		(850		)	1,558				19,632		(5,324		)	(17,113		)	—		—			88,063
Total	116,060		(850		)	1,558				19,632		(5,324		)	(17,113		)	—		(25,900		)	88,063
Equity securities available for sale:
Common stocks	1,559		—			—				—		—			—			—		—			1,559
Preferred stocks	54,713		23,535			31,633				19,542		(39,977		)	—			—		—			89,446
Total	56,272		23,535			31,633				19,542		(39,977		)	—			—		—			91,005
Arbitrage trading account	353		(353		)	—				3,187		—			—			—		—			3,187
Total	$	172,685	$	22,332		$	33,191			$	42,361	$	(45,301	)	$	(17,113	)	$	—	$	(25,900	)	$	182,255