Investments (Tables)

3 Months Ended

Mar. 31, 2013

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:

	March 31, 2013
(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	$	314.0	$	8.1	$	0.6	$	321.5	$	—
Foreign government		299.7		6.0		0.1		305.6		—
Municipal		988.2		89.3		1.4		1,076.1		—
Corporate		3,443.3		268.8		13.3		3,698.8		9.2
Residential mortgage-backed		720.3		37.3		3.3		754.3		2.0
Commercial mortgage-backed		340.6		18.8		0.6		358.8		—
Asset-backed		204.5		3.9		—		208.4		—
Total fixed maturities	$	6,310.6	$	432.2	$	19.3	$	6,723.5	$	11.2
Equity securities	$	391.2	$	46.0	$	2.2	$	435.0	$	—

	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	$	—

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.

(in millions)	March 31, 2013
	Amortized		Fair
	Cost		Value
Due in one year or less	$	430.2	$	437.4
Due after one year through five years		2,216.7		2,344.4
Due after five years through ten years		1,718.1		1,879.3
Due after ten years		680.2		740.9
		5,045.2		5,402.0
Mortgage-backed and asset-backed securities		1,265.4		1,321.5
Total fixed maturities	$	6,310.6	$	6,723.5

Fixed Maturities and Equity Securities in Unrealized Loss Position

The following tables provide information about the Company’s fixed maturities and equity securities that were in an unrealized loss position at March 31, 2013 and December 31, 2012.

	March 31, 2013
	12 months or less				Greater than 12 months				Total
(in millions)	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	$	0.5	$	98.1	$	0.1	$	6.5	$	0.6	$	104.6
Foreign governments		—		23.9		0.1		0.4		0.1		24.3
Municipal		0.7		65.5		0.6		16.3		1.3		81.8
Corporate		2.1		181.3		6.9		34.4		9.0		215.7
Residential mortgage-backed		0.8		66.7		2.0		9.5		2.8		76.2
Commercial mortgage-backed		0.5		52.4		0.1		4.9		0.6		57.3
Asset-backed		—		24.0		—		0.2		—		24.2
Total investment grade		4.6		511.9		9.8		72.2		14.4		584.1
Below investment grade:
Municipal		—		—		0.1		3.4		0.1		3.4
Corporate		0.9		30.0		3.4		35.5		4.3		65.5
Residential mortgage-backed		0.1		0.8		0.4		2.2		0.5		3.0
Total below investment grade		1.0		30.8		3.9		41.1		4.9		71.9
Total fixed maturities		5.6		542.7		13.7		113.3		19.3		656.0
Equity securities		1.4		15.4		0.8		7.9		2.2		23.3
Total	$	7.0	$	558.1	$	14.5	$	121.2	$	21.5	$	679.3

	December 31, 2012
	12 months or less				Greater than 12 months				Total
(in millions)	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

Proceeds from Sale of Available-for-Sale Securities

The proceeds from sales of available-for-sale securities and gross realized gains and losses on those sales, were as follows:

	Three Months Ended March 31,
	2013						2012
(in millions)	Proceeds from Sales		Gross Gains		Gross Losses		Proceeds from Sales		Gross Gains		Gross Losses
Fixed maturities	$	137.2	$	1.6	$	0.6	$	279.2	$	4.7	$	1.1
Equity securities	$	34.5	$	6.6	$	—	$	0.7	$	—	$	0.2

Rollforward of Cumulative Amounts Related to Credit Loss Portion of OTTI Losses

The following table provides rollforwards of the cumulative amounts related to the Company’s credit loss portion of the OTTI losses on fixed maturity securities for which the non-credit portion of the loss is included in other comprehensive income.

	Three Months Ended March 31,
(in millions)	2013			2012
Credit losses at beginning of period	$	8.6		$	14.5
Credit losses for which an OTTI was not previously recognized		0.2			0.1
Additional credit losses on securities for which an OTTI was previously recognized		0.2			0.3
Reductions for securities sold, matured or called		(0.4	)		(1.4	)
Credit losses at end of period	$	8.6		$	13.5