Segment Information (Tables)

12 Months Ended

Dec. 31, 2015

Segment Reporting [Abstract]

Segment Information

This table summarizes segment information:

(Dollars in millions)	Years ended December 31,
	2015			2014			2013
Revenues:
Commercial lines insurance
Commercial casualty	$	1,010		$	938		$	856
Commercial property	815			728			623
Commercial auto	561			528			479
Workers' compensation	367			370			365
Other commercial	243			292			313
Commercial lines insurance premiums	2,996			2,856			2,636
Fee revenues	4			4			3
Total commercial lines insurance	3,000			2,860			2,639
Personal lines insurance
Personal auto	506			476			443
Homeowner	463			443			403
Other personal	128			122			115
Personal lines insurance premiums	1,097			1,041			961
Fee revenues	3			2			1
Total personal lines insurance	1,100			1,043			962
Excess and surplus lines insurance	168			148			116
Fee revenues	1			—			—
Total excess and surplus lines insurance	169			148			116
Life insurance premiums	209			198			189
Separate account investment management fees	5			6			4
Total life insurance	214			204			193
Investments
Investment income, net of expenses	572			549			529
Realized investment gains, net	70			133			83
Total investment revenue	642			682			612
Other	17			8			9
Total revenues	$	5,142		$	4,945		$	4,531
Income (loss) before income taxes:
Insurance underwriting results
Commercial lines insurance	$	345		$	146		$	186
Personal lines insurance	(12		)	10			33
Excess and surplus lines insurance	51			30			14
Life insurance	(2		)	(5		)	9
Investments	556			599			532
Other	(57		)	(59		)	(60		)
Total income before income taxes	$	881		$	721		$	714
	December 31,			December 31,
Identifiable assets:	2015			2014
Property casualty insurance	$	2,717		$	2,656
Life insurance	1,325			1,316
Investments	14,485			14,441
Other	361			335
Total	$	18,888		$	18,748