Segment Information (Tables)

6 Months Ended

Jun. 30, 2017

Segment Reporting [Abstract]

Reconciliation of operating results by reportable segment

The following tables present the Company's operating results by reportable segment:

	Three Months Ended
	June 30, 2017							June 30, 2016
	Property & Casualty		Other		Total			Property & Casualty			Other		Total
(Amounts in millions)
Net premiums earned	$	789.0	$	8.7	$	797.7		$	768.6		$	10.7	$	779.3
Less:
Losses and loss adjustment expenses	584.2		4.4		588.6			589.4			5.7		595.1
Underwriting expenses	187.3		4.0		191.3			193.4			4.2		197.6
Underwriting gain (loss)	17.5		0.3		17.8			(14.2		)	0.8		(13.4		)
Investment income					31.9								31.5
Net realized investment gains					21.1								45.4
Other income					2.1								1.9
Interest expense					(4.2		)						(1.0		)
Pre-tax income					$	68.8							$	64.3
Net income					$	51.6							$	48.9

	Six Months Ended
	June 30, 2017								June 30, 2016
	Property & Casualty			Other		Total			Property & Casualty			Other		Total
(Amounts in millions)
Net premiums earned	$	1,569.7		$	17.7	$	1,587.4		$	1,524.4		$	22.0	$	1,546.4
Less:
Losses and loss adjustment expenses	1,186.0			9.3		1,195.3			1,177.4			11.8		1,189.2
Underwriting expenses	391.1			7.9		399.0			391.3			9.1		400.4
Underwriting (loss) gain	(7.4		)	0.5		(6.9		)	(44.3		)	1.1		(43.2		)
Investment income						63.1								61.1
Net realized investment gains						45.6								70.4
Other income						4.3								4.0
Interest expense						(6.7		)						(1.9		)
Pre-tax income						$	99.4							$	90.4
Net income						$	78.6							$	72.2

Schedule direct premiums attributable to segment

The following tables present the Company’s net premiums earned and direct premiums written by line of insurance business:

	Three Months Ended
	June 30, 2017						June 30, 2016
	Property & Casualty		Other		Total		Property & Casualty		Other		Total
(Amounts in millions)
Private passenger automobile	$	617.3	$	—	$	617.3	$	607.1	$	—	$	607.1
Homeowners	108.3		—		108.3		102.0		—		102.0
Commercial automobile	42.4		—		42.4		39.9		—		39.9
Other	21.0		8.7		29.7		19.6		10.7		30.3
Net premiums earned	$	789.0	$	8.7	$	797.7	$	768.6	$	10.7	$	779.3
Private passenger automobile	$	600.1	$	—	$	600.1	$	595.4	$	—	$	595.4
Homeowners	122.7		—		122.7		116.3		—		116.3
Commercial automobile	45.1		—		45.1		42.4		—		42.4
Other	24.2		8.5		32.7		23.0		6.9		29.9
Direct premiums written	$	792.1	$	8.5	$	800.6	$	777.1	$	6.9	$	784.0

	Six Months Ended
	June 30, 2017						June 30, 2016
	Property & Casualty		Other		Total		Property & Casualty		Other		Total
(Amounts in millions)
Private passenger automobile	$	1,230.5	$	—	$	1,230.5	$	1,206.1	$	—	$	1,206.1
Homeowners	214.0		—		214.0		201.5		—		201.5
Commercial automobile	83.7		—		83.7		78.6		—		78.6
Other	41.5		17.7		59.2		38.2		22.0		60.2
Net premiums earned	$	1,569.7	$	17.7	$	1,587.4	$	1,524.4	$	22.0	$	1,546.4
Private passenger automobile	$	1,239.1	$	—	$	1,239.1	$	1,227.2	$	—	$	1,227.2
Homeowners	226.5		—		226.5		215.4		—		215.4
Commercial automobile	88.1		—		88.1		83.3		—		83.3
Other	47.0		14.2		61.2		43.9		14.3		58.2
Direct premiums written	$	1,600.7	$	14.2	$	1,614.9	$	1,569.8	$	14.3	$	1,584.1