Nature of Operations (Details) (Property and casualty insurance operations)	Mar. 31, 2013 States
Property and casualty insurance operations
Product information
Number of states in which the Property and Casualty Group operates	11

The number of states the entity operates in as of the balance sheet date.

No definition available.

Name:	us-gaap_NumberOfStatesInWhichEntityOperates
Namespace Prefix:	us-gaap_
Data Type:	xbrli:integerItemType
Balance Type:	na
Period Type:	instant