v2.4.0.8

Investments (Details 1) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
U.S. Treasury obligations [Member]
Fixed maturities, available for sale
Amortized Cost	$ 206,778	$ 191,642
Due in one year or less	24,239
Due after one year through five years	135,973
Due after five years through ten years	49,745
Due after ten years	3,865
Total Fair Value	213,822	205,857
U.S. Government-sponsored enterprise obligations [Member]
Fixed maturities, available for sale
Amortized Cost	53,486	52,110
Due in one year or less	0
Due after one year through five years	49,356
Due after five years through ten years	7,340
Due after ten years	229
Total Fair Value	56,925	56,947
State and municipal bonds [Member]
Fixed maturities, available for sale
Amortized Cost	1,204,739	1,134,744
Due in one year or less	52,665
Due after one year through five years	418,391
Due after five years through ten years	493,559
Due after ten years	288,557
Total Fair Value	1,253,172	1,219,979
Corporate debt [Member]
Fixed maturities, available for sale
Amortized Cost	1,502,700	1,375,880
Due in one year or less	104,583
Due after one year through five years	702,834
Due after five years through ten years	685,649
Due after ten years	53,826
Total Fair Value	1,546,892	1,470,524
Residential mortgage-backed securities [Member]
Fixed maturities, available for sale
Amortized Cost	263,844	272,990
Total Fair Value	272,233	289,850
Agency commercial mortgage-backed securities [Member]
Fixed maturities, available for sale
Amortized Cost	43,696	57,234
Total Fair Value	44,449	59,464
Other commercial mortgage-backed securities [Member]
Fixed maturities, available for sale
Amortized Cost	67,861	69,062
Total Fair Value	70,865	74,106
Other asset-backed securities [Member]
Fixed maturities, available for sale
Amortized Cost	75,843	70,670
Total Fair Value	76,075	71,272
Debt Securities [Member]
Fixed maturities, available for sale
Amortized Cost	3,418,947	3,224,332
Total Fair Value	$ 3,534,433	$ 3,447,999

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