v2.3.0.15

Investments (Schedule Of Amortized Cost And Estimated Fair Value Of Fixed Maturities By Contractual Maturity Date) (Details) (USD $) In Thousands	Sep. 30, 2011	Dec. 31, 2010
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less, Amortized Cost	$ 213,328
Due after one year through five years, Amortized Cost	1,179,686
Due after five years through ten years, Amortized Cost	1,835,956
Due after ten years, Amortized Cost	1,585,752
Due in one year or less, Estimated Fair Value	216,747
Due after one year through five years, Estimated Fair Value	1,254,046
Due after five years through ten years, Estimated Fair Value	1,979,274
Due after ten years, Estimated Fair Value	1,691,011
Amortized Cost sub-total	4,814,722
Fair Value sub-total	5,141,078
Fixed maturities, amortized cost	5,223,979	5,256,980
Total fixed maturities, Estimated Fair Value	5,576,584	5,431,226
Residential Mortgage-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	392,534
Estimated Fair Value	417,954
Fixed maturities, amortized cost	392,534	409,415
Total fixed maturities, Estimated Fair Value	417,954	425,563
Asset-Backed Securities [Member]
Schedule of Available-for-sale Securities [Line Items]
Amortized Cost	16,723
Estimated Fair Value	17,552
Fixed maturities, amortized cost	16,723	21,704
Total fixed maturities, Estimated Fair Value	$ 17,552	$ 22,756

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