Investments (Details Textual) (USD $)	12 Months Ended
	Dec. 31, 2012 Security	Dec. 31, 2011
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	$ 829,577,000	$ 815,999,000
Investments (Textual) [Abstract]
Available for sale securities	115,300,000	342,600,000
Net realized gains	9,400,000	11,000,000
Net unrealized holding gains	300,000	0
Percentage of fixed maturity securities	10.00%	10.00%
Fixed income securities with fair values	29,500,000	29,900,000
Number of available for sale securities in unrealized loss position for less than twelve months	2,110
Number of available for sale securities in unrealized loss position for period of twelve months or greater	5
Number of available for sale securities in unrealized loss position for period of less than twelve	144
Interest rate swap [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Realized gain from trading securities	300,000
Fixed maturity securities [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	340,700,000	326,900,000
Fixed Maturities industrial sector [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	165,200,000	149,200,000
Fixed Maturities financial sector [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	127,200,000	110,300,000
Utility [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	39,500,000	57,400,000
Foreign agencies and other securities [Member]
Fair Value Investments Entities That Calculate Net Asset Value Per Share [Line Items]
Fixed maturity securities, at fair value	$ 8,800,000	$ 10,000,000