Reinsurance Ceded Premiums Earned by type (Details) (USD $) In Thousands, unless otherwise specified	3 Months Ended		6 Months Ended
	Jun. 30, 2014	Jun. 30, 2013	Jun. 30, 2014	Jun. 30, 2013
Ceded Premiums Earned by type [Line Items]
Ceded Premiums Written	$ (136,792)	$ (117,146)	$ (140,643)	$ (118,889)
Increase (Decrease) in Ceded Unearned Premiums	103,753	88,217	76,627	62,381
Ceded Premiums Earned	(33,039)	(28,929)	(64,016)	(56,508)
Excess of Loss Product Line [Member]
Ceded Premiums Earned by type [Line Items]
Ceded Premiums Written	(131,213)	(112,387)	(131,274)	(111,083)
Equipment and Identity Theft Product Line [Member]
Ceded Premiums Earned by type [Line Items]
Ceded Premiums Written	(1,156)	(684)	(1,917)	(1,155)
Flood Product Line [Member]
Ceded Premiums Earned by type [Line Items]
Ceded Premiums Written	$ (4,423)	$ (4,075)	$ (7,452)	$ (6,651)