Reinsurance (Details) (USD $)	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011	Jun. 01, 2012 Maximum [Member] Unaffiliated Private Reinsurers [Member]	Jun. 01, 2012 Maximum [Member] Florida Hurricane Catastrophe Fund [Member] Mandatory Layer [Member]	Jun. 01, 2012 Property Business [Member]	Jun. 01, 2012 Property Business [Member] Maximum [Member]
Reinsurance Premiums for Insurance Companies, by Product Segment [Line Items]
Aggregate Coverage for Covered Losses Under Reinsurance Contract					$ 184,218,000	$ 353,101,000		$ 3,400,000
Aggregate Coverage for Covered Losses Under Reinsurance Contract, Excess Coverage Per Million Dollars of Risk								1,700,000
Reinsurance Agreement, Threshold For Excess Loss Coverage							1,000,000
Resinstatement of Full Coverage In the Event of Exhausted Coverage Due to Loss Recoveries, Percent Additional Premium							50.00%
Insurance Commissions and Fees, Flood Program	151,000	109,000	392,000	302,000
Reinsurance Costs and Recoveries, Net	61,000	13,963,000	1,623,000	20,542,000
Increase (Decrease) in Reinsurance Recoverable		$ 12,738,000	$ (1,445,000)	$ (20,661,000)