INVESTMENT OPERATIONS (Tables)

12 Months Ended

Dec. 31, 2012

INVESTMENT OPERATIONS

Summary of major categories of net investment income

	For The Year Ended December 31,
	2012		2011		2010
	(Dollars In Thousands)
Fixed maturities	$	1,453,018	$	1,414,965	$	1,301,047
Equity securities	20,740		20,595		17,836
Mortgage loans	349,845		336,541		310,988
Investment real estate	3,289		3,458		3,180
Short-term investments	62,887		72,137		77,185
	1,889,779		1,847,696		1,710,236
Other investment expenses	100,441		94,252		85,391
Net investment income	$	1,789,338	$	1,753,444	$	1,624,845

Summary of net realized investment gains (losses) for invested assets

	For The Year Ended December 31,
	2012			2011			2010
	(Dollars In Thousands)
Fixed maturities	$	67,669		$	80,044		$	51,816
Equity securities	(45		)	9,136			6,489
Impairments on fixed maturity securities	(58,144		)	(47,321		)	(39,550		)
Impairments on equity securities	—			—			(1,815		)
Modco trading portfolio	177,986			164,224			109,399
Other investments	(12,774		)	(5,651		)	(9,283		)
Total realized gains (losses) - investments	$	174,692		$	200,432		$	117,056

Schedule of amortized cost and fair value of the Company's investments classified as available-for-sale

The amortized cost and fair value of the Company’s investments classified as available-for-sale as of December 31, are as follows:

			Gross		Gross					Total OTTI
	Amortized		Unrealized		Unrealized			Fair		Recognized
	Cost		Gains		Losses			Value		in OCI(1)
	(Dollars In Thousands)
2012
Fixed maturities:
Bonds
Residential mortgage-backed securities	$	1,766,260	$	92,417	$	(19,347	)	$	1,839,330	$	(406	)
Commercial mortgage-backed securities	797,844		72,577		(598		)	869,823		—
Other asset-backed securities	1,023,649		12,788		(61,424		)	975,013		(241		)
U.S. government-related securities	1,097,501		71,536		(591		)	1,168,446		—
Other government-related securities	93,565		7,258		(45		)	100,778		—
States, municipals, and political subdivisions	1,188,019		255,898		(264		)	1,443,653		—
Corporate bonds	17,687,164		2,726,858		(48,395		)	20,365,627		(5,488		)
	23,654,002		3,239,332		(130,664		)	26,762,670		(6,135		)
Equity securities	352,272		11,881		(9,993		)	354,160		—
Short-term investments	97,852		—		—			97,852		—
	$	24,104,126	$	3,251,213	$	(140,657	)	$	27,214,682	$	(6,135	)
2011
Fixed maturities:
Bonds
Residential mortgage-backed securities	$	2,340,172	$	82,574	$	(85,702	)	$	2,337,044	$	(47,652	)
Commercial mortgage-backed securities	530,283		24,473		(4,229		)	550,527		—
Other asset-backed securities	997,398		6,529		(90,898		)	913,029		(6,559		)
U.S. government-related securities	1,150,525		65,212		(58		)	1,215,679		—
Other government-related securities	88,058		4,959		—			93,017		—
States, municipals, and political subdivisions	1,154,307		173,406		—			1,327,713		—
Corporate bonds	16,888,423		1,922,038		(249,870		)	18,560,591		1,787
	23,149,166		2,279,191		(430,757		)	24,997,600		(52,424		)
Equity securities	286,537		5,430		(16,595		)	275,372		(74		)
Short-term investments	15,629		—		—			15,629		—
	$	23,451,332	$	2,284,621	$	(447,352	)	$	25,288,601	$	(52,498	)

(1)These amounts are included in the gross unrealized gains and gross unrealized losses columns above.

Schedule of amortized cost and fair value of the Company's investments classified as held-to-maturity

The amortized cost and fair value of the Company’s investments classified as held-to-maturity as of December 31, are as follows:

			Gross		Gross				Total OTTI
	Amortized		Unrealized		Unrealized		Fair		Recognized
	Cost		Gains		Losses		Value		in OCI
2012
Fixed maturities:
Other	$	300,000	$	19,163	$	—	$	319,163	$	—
	$	300,000	$	19,163	$	—	$	319,163	$	—

Schedule of amortized cost and fair value of available-for-sale and held-to-maturity fixed maturities, by expected maturity

The amortized cost and fair value of available-for-sale and held-to-maturity fixed maturities as of December 31, 2012, by expected maturity, are shown below. Expected maturities of securities without a single maturity date are allocated based on estimated rates of prepayment that may differ from actual rates of prepayment.

	Available-for-sale				Held-to-Maturity
	Amortized		Fair		Amortized		Fair
	Cost		Value		Cost		Value
	(Dollars In Thousands)				(Dollars In Thousands)
Due in one year or less	$	452,876	$	459,845	$	—	$	—
Due after one year through five years	4,568,417		4,996,310		—		—
Due after five years through ten years	6,283,158		6,967,782		—		—
Due after ten years	12,349,551		14,338,733		300,000		319,163
	$	23,654,002	$	26,762,670	$	300,000	$	319,163

Schedule of credit losses on debt securities held by the Company for which a portion of an other-than-temporary impairment was recognized in other comprehensive income (loss)

	For The Year Ended December 31,
	2012		2011			2010
	(Dollars In Thousands)
Beginning balance	$	69,476	$	39,275		$	25,066
Additions for newly impaired securities	26,544		12,699			26,893
Additions for previously impaired securities	25,217		20,591			4,964
Reductions for previously impaired securities due to a change in expected cash flows	—		—			—
Reductions for previously impaired securities that were sold in the current period	—		(3,089		)	(17,648		)
Other	—		—			—
Ending balance	$	121,237	$	69,476		$	39,275

Schedule of investments' gross unrealized losses and fair value of the Company's investments that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position

The following table includes the gross unrealized losses and fair value of the Company’s investments that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of December 31, 2012:

	Less Than 12 Months					12 Months or More					Total
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Loss			Value		Loss			Value		Loss
	(Dollars In Thousands)
Residential mortgage-backed securities	$	100,412	$	(9,578	)	$	166,000	$	(9,769	)	$	266,412	$	(19,347	)
Commercial mortgage-backed securities	50,506		(598		)	—		—			50,506		(598		)
Other asset-backed securities	479,223		(28,179		)	242,558		(33,245		)	721,781		(61,424		)
U.S. government-related securities	106,806		(591		)	—		—			106,806		(591		)
Other government-related securities	14,955		(45		)	—		—			14,955		(45		)
States, municipalities, and political subdivisions	11,526		(264		)	—		—			11,526		(264		)
Corporate bonds	775,593		(23,630		)	363,128		(24,765		)	1,138,721		(48,395		)
Equities	35,059		(5,150		)	21,754		(4,843		)	56,813		(9,993		)
	$	1,574,080	$	(68,035	)	$	793,440	$	(72,622	)	$	2,367,520	$	(140,657	)

The following table includes the gross unrealized losses and fair value of the Company’s investments that are not deemed to be other-than-temporarily impaired, aggregated by investment category and length of time that individual securities have been in a continuous unrealized loss position as of December 31, 2011:

	Less Than 12 Months					12 Months or More					Total
	Fair		Unrealized			Fair		Unrealized			Fair		Unrealized
	Value		Loss			Value		Loss			Value		Loss
	(Dollars In Thousands)
Residential mortgage-backed securities	$	276,216	$	(15,308	)	$	524,251	$	(70,394	)	$	800,467	$	(85,702	)
Commercial mortgage-backed securities	78,893		(4,229		)	—		—			78,893		(4,229		)
Other asset-backed securities	531,653		(32,074		)	190,639		(58,824		)	722,292		(90,898		)
U.S. government-related securities	21,311		(58		)	—		—			21,311		(58		)
Corporate bonds	1,870,256		(131,953		)	523,913		(117,917		)	2,394,169		(249,870		)
Equities	50,638		(8,436		)	22,095		(8,159		)	72,733		(16,595		)
	$	2,828,967	$	(192,058	)	$	1,260,898	$	(255,294	)	$	4,089,865	$	(447,352	)

Summary of change in unrealized gains (losses), net of income tax, on fixed maturity and equity securities, classified as available-for-sale

	For The Year Ended December 31,
	2012		2011			2010
	(Dollars In Thousands)
Fixed maturities	$	819,152	$	761,738		$	696,942
Equity securities	8,484		(13,292		)	9,701