Nature of Operations (Details) (Property and Casualty Group)	12 Months Ended
	Dec. 31, 2014
Product information
Number of states in which the Property and Casualty Group operates	12
Private passenger automobile
Product information
Percentage of property and casualty direct written premiums	43.00%
Homeowners
Product information
Percentage of property and casualty direct written premiums	27.00%
Commercial multi-peril
Product information
Percentage of property and casualty direct written premiums	13.00%
Commercial automobile
Product information
Percentage of property and casualty direct written premiums	7.00%
Workers compensation
Product information
Percentage of property and casualty direct written premiums	7.00%