Commitments and Contingencies (Details) (USD $) In Millions, unless otherwise specified	Sep. 30, 2012
Commitments and Contingencies (Textual) [Abstract]
Letters of credit issued and outstanding	$ 69.8
Irrevocable letters of credit [Member]
Commitments and Contingencies (Textual) [Abstract]
Letters of credit issued and outstanding	5.8
Benefit of the Vermont Department of Banking, Insurance, Securities and Health Care Administration	2.5
Contingent payment obligation	2.5
Letters of credit issued to other parties	$ 0.8