Fair Value of Financial Instruments (Details 1) (USD $) In Thousands, unless otherwise specified	3 Months Ended		9 Months Ended
	Sep. 30, 2012	Sep. 30, 2011	Sep. 30, 2012	Sep. 30, 2011
Financial Assets
Beginning balance	$ 122,063	$ 50,493	$ 93,173	$ 46,585
Transfers into Level 3	62,899	17,019	89,643	34,408
Transfers out of Level 3			(50,707)	(13,725)
Total gains or losses
Net realized gains (losses) included in net income	2,282		4,590
Net unrealized gains (losses) included in other comprehensive income	19	3,394	1,130	4,241
Purchases			50,000
Issuances
Sales
Settlements
Paydowns, maturities and distributions	(2,405)	(321)	(2,971)	(924)
Ending balance	184,858	70,585	184,858	70,585
Municipal Bonds [Member]
Financial Assets
Beginning balance
Transfers into Level 3	12,297		12,297
Transfers out of Level 3
Total gains or losses
Net realized gains (losses) included in net income
Net unrealized gains (losses) included in other comprehensive income
Purchases
Issuances
Sales
Settlements
Paydowns, maturities and distributions
Ending balance	12,297		12,297
Corporate bonds [Member]
Financial Assets
Beginning balance	56,459	49,285	88,256	45,244
Transfers into Level 3	29,558	15,098	47,798	32,487
Transfers out of Level 3			(50,707)	(13,725)
Total gains or losses
Net realized gains (losses) included in net income			0
Net unrealized gains (losses) included in other comprehensive income	(31)	3,388	915	4,233
Purchases
Issuances
Sales
Settlements
Paydowns, maturities and distributions	(169)	(261)	(445)	(729)
Ending balance	85,817	67,510	85,817	67,510
Other mortgage-backed securities [Member]
Financial Assets
Beginning balance	12,911	824	4,532	945
Transfers into Level 3	21,044	1,921	29,548	1,921
Transfers out of Level 3			0
Total gains or losses
Net realized gains (losses) included in net income	(2)		(2)
Net unrealized gains (losses) included in other comprehensive income	95	6	260	20
Purchases
Issuances
Sales
Settlements
Paydowns, maturities and distributions	(160)	(60)	(450)	(195)
Ending balance	33,888	2,691	33,888	2,691
Total Fixed Maturities [Member]
Financial Assets
Beginning balance	69,370	50,109	92,788	46,189
Transfers into Level 3	62,899	17,019	89,643	34,408
Transfers out of Level 3			(50,707)	(13,725)
Total gains or losses
Net realized gains (losses) included in net income	(2)		(2)
Net unrealized gains (losses) included in other comprehensive income	64	3,394	1,175	4,253
Purchases
Issuances
Sales
Settlements
Paydowns, maturities and distributions	(329)	(321)	(895)	(924)
Ending balance	132,002	70,201	132,002	70,201
Equity securities [Member]
Financial Assets
Beginning balance	385	384	385	396
Transfers into Level 3
Transfers out of Level 3
Total gains or losses
Net realized gains (losses) included in net income
Net unrealized gains (losses) included in other comprehensive income	(45)		(45)	(12)
Purchases
Issuances
Sales
Settlements
Paydowns, maturities and distributions
Ending balance	340	384	340	384
Other Investments [Member]
Financial Assets
Beginning balance	52,308
Transfers into Level 3
Transfers out of Level 3
Total gains or losses
Net realized gains (losses) included in net income	2,284		4,592
Net unrealized gains (losses) included in other comprehensive income
Purchases			50,000
Issuances
Sales
Settlements
Paydowns, maturities and distributions	(2,076)		(2,076)
Ending balance	$ 52,516		$ 52,516