Condensed Consolidated Statements of Income (USD $) In Millions, except Per Share data, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2014	Sep. 30, 2013	Sep. 30, 2014	Sep. 30, 2013
Revenues [Abstract]
Earned premiums	$ 1,071	$ 992	$ 3,157	$ 2,877
Investment income, net of expenses	138	133	409	392
Realized investment gains, net	65	22	101	77
Fee revenues	3	2	9	6
Other revenues	3	3	7	7
Total revenues	1,280	1,152	3,683	3,359
Benefits and Expenses
Insurance losses and policyholder benefits	686	642	2,181	1,841
Underwriting, acquisition and insurance expenses	319	312	967	919
Interest expense	13	13	40	40
Other operating expenses	3	3	10	12
Total benefits and expenses	1,021	970	3,198	2,812
Income Before Income Taxes	259	182	485	547
Provision for Income Taxes
Current	68	46	106	137
Deferred	8	5	21	15
Total provision for income taxes	76	51	127	152
Net Income	$ 183	$ 131	$ 358	$ 395
Per Common Share
Net income-basic (in USD per share)	$ 1.12	$ 0.80	$ 2.19	$ 2.42
Net income-diluted (in USD per share)	$ 1.11	$ 0.79	$ 2.17	$ 2.39