INVESTMENTS (Tables)

12 Months Ended

Dec. 31, 2012

Amortized Cost And Fair Value Of Available-For-Sale Fixed Maturities And Cost And Fair Value Of Equity Securities

The amortized cost and fair value of available-for-sale fixed maturities and the cost and fair value of equity securities were as follows:

DECEMBER 31, 2012
(in millions)
	Amortized Cost or Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		OTTI Unrealized Losses
Fixed maturities:
U.S. Treasury and government agencies	$	317.2	$	8.8	$	0.4	$	325.6	$	—
Foreign government		348.5		4.6		0.2		352.9		—
Municipal		1,010.2		87.2		1.1		1,096.3		—
Corporate		3,512.8		275.4		14.8		3,773.4		9.3
Residential mortgage-backed		769.0		39.4		3.2		805.2		1.7
Commercial mortgage-backed		373.3		23.2		0.3		396.2		—
Asset-backed		198.5		4.1		—		202.6		—
Total fixed maturities	$	6,529.5	$	442.7	$	20.0	$	6,952.2	$	11.0
Equity securities	$	299.0	$	21.6	$	4.8	$	315.8	$	—

DECEMBER 31, 2011
(in millions)
	Amortized Cost or Cost		Gross Unrealized Gains		Gross Unrealized Losses		Fair Value		OTTI Unrealized Losses
Fixed maturities:
U.S. Treasury and government agencies	$	261.7	$	7.8	$	0.2	$	269.3	$	—
Foreign government		239.1		0.4		0.5		239.0		—
Municipal		964.5		67.4		3.9		1,028.0		—
Corporate		3,218.2		197.7		40.3		3,375.6		13.8
Residential mortgage-backed		816.1		40.9		8.4		848.6		6.1
Commercial mortgage-backed		384.1		15.0		1.0		398.1		—
Asset-backed		125.0		1.8		0.7		126.1		—
Total fixed maturities	$	6,008.7	$	331.0	$	55.0	$	6,284.7	$	19.9
Equity securities	$	239.9	$	15.3	$	8.8	$	246.4	$	—

Maturities of Available-For-Sale Debt Securities

The amortized cost and fair value by maturity periods for fixed maturities are shown below. Actual maturities may differ from contractual maturities because borrowers may have the right to call or prepay obligations with or without call or prepayment penalties, or the Company may have the right to put or sell the obligations back to the issuers.

DECEMBER 31	2012
(in millions)
	Amortized Cost		Fair Value
Due in one year or less	$	413.0	$	419.5
Due after one year through five years		2,319.4		2,442.8
Due after five years through ten years		1,750.9		1,919.3
Due after ten years		705.4		766.6
		5,188.7		5,548.2
Mortgage-backed and asset-backed securities		1,340.8		1,404.0
Total fixed maturities	$	6,529.5	$	6,952.2

Unrealized Gains And Losses On Available-For-Sale And Other Securities

Unrealized gains and losses on available-for-sale and other securities are summarized in the following table.

FOR THE YEARS ENDED DECEMBER 31
(in millions)
2012	Fixed Maturities			Equity Securities And Other			Total
Net appreciation, beginning of year	$	300.2		$	8.5		$	308.7
Net appreciation on available-for-sale securities and derivative instruments		140.7			10.6			151.3
Portion of OTTI losses recognized in other comprehensive income		12.2			—			12.2
Provision for deferred income taxes		(43.0	)		(3.2	)		(46.2	)
		109.9			7.4			117.3
Net appreciation, end of year	$	410.1		$	15.9		$	426.0
2011
Net appreciation, beginning of year	$	210.3		$	8.0		$	218.3
Net appreciation (depreciation) on available-for-sale securities and derivative instruments		66.4			(1.3	)		65.1
Portion of OTTI losses recognized in other comprehensive income		10.5			—			10.5
Benefit for deferred income taxes		13.0			1.8			14.8
		89.9			0.5			90.4
Net appreciation, end of year	$	300.2		$	8.5		$	308.7
2010
Net appreciation, beginning of year	$	97.8		$	9.9		$	107.7
Net appreciation (depreciation) on available-for-sale securities		101.1			(3.3	)		97.8
Portion of OTTI losses recognized in other comprehensive income		6.9			—			6.9
Benefit for deferred income taxes		4.5			1.4			5.9
		112.5			(1.9	)		110.6
Net appreciation, end of year	$	210.3		$	8.0		$	218.3

Fixed Maturities And Equity Securities In An Unrealized Loss Position

The following tables provide information about the Company’s fixed maturities and equity securities that are in an unrealized loss position at December 31, 2012 and 2011:

DECEMBER 31, 2012
(in millions)
	12 months or less				Greater than 12 months				Total
	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
Fixed maturities:
Investment grade:
U.S. Treasury and government agencies	$	0.2	$	89.5	$	0.2	$	8.5	$	0.4	$	98.0
Foreign governments		0.2		81.2		—		0.4		0.2		81.6
Municipal		0.5		61.9		0.6		24.0		1.1		85.9
Corporate		1.8		224.8		6.6		59.0		8.4		283.8
Residential mortgage-backed		0.5		47.3		2.0		9.4		2.5		56.7
Commercial mortgage-backed		0.2		29.9		0.1		4.9		0.3		34.8
Asset-backed		—		11.4		—		0.3		—		11.7
Total investment grade		3.4		546.0		9.5		106.5		12.9		652.5
Below investment grade:
Municipal		—		—		—		2.0		—		2.0
Corporate		1.1		26.6		5.3		50.6		6.4		77.2
Residential mortgage-backed		0.1		1.6		0.6		2.5		0.7		4.1
Total below investment grade		1.2		28.2		5.9		55.1		7.1		83.3
Total fixed maturities		4.6		574.2		15.4		161.6		20.0		735.8
Equity securities		4.8		74.4		—		—		4.8		74.4
Total	$	9.4	$	648.6	$	15.4	$	161.6	$	24.8	$	810.2
DECEMBER 31, 2011
(in millions)
	12 months or less				Greater than 12 months				Total
	Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value		Gross Unrealized Losses		Fair Value
Fixed maturities:
Investment grade:
U.S. Treasury and government agencies	$	0.2	$	57.7	$	—	$	—	$	0.2	$	57.7
Foreign governments		0.5		148.8		—		—		0.5		148.8
Municipal		0.5		28.0		3.4		58.8		3.9		86.8
Corporate		19.9		699.6		8.2		35.6		28.1		735.2
Residential mortgage-backed		5.1		115.8		2.4		9.9		7.5		125.7
Commercial mortgage-backed		0.7		58.0		0.3		4.6		1.0		62.6
Asset-backed		0.2		67.6		—		—		0.2		67.6
Total investment grade		27.1		1,175.5		14.3		108.9		41.4		1,284.4
Below investment grade:
Corporate		8.5		118.0		3.7		14.7		12.2		132.7
Residential mortgage-backed		0.9		8.0		—		—		0.9		8.0
Asset-backed		0.5		0.9		—		—		0.5		0.9
Total below investment grade		9.9		126.9		3.7		14.7		13.6		141.6
Total fixed maturities		37.0		1,302.4		18.0		123.6		55.0		1,426.0
Equity securities		8.8		87.2		—		—		8.8		87.2
Total	$	45.8	$	1,389.6	$	18.0	$	123.6	$	63.8	$	1,513.2