v2.4.0.6

Summary of Available for Sale Fixed Securities by Contractual Maturity (Detail) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2012	Dec. 31, 2011
Schedule of Available-for-sale Securities [Line Items]
Total fixed maturities	$ 1,773,571	$ 1,382,863
Total fixed maturities	1,825,759	1,394,243
Fixed maturities
Schedule of Available-for-sale Securities [Line Items]
Due in one year or less	14,363
Due after one through five years	373,115
Due after five through ten years	763,908
Due after ten years	257,264
Mortgage backed securities	364,921
Total fixed maturities	1,773,571
Due in one year or less	14,907
Due after one through five years	364,853
Due after five through ten years	794,965
Due after ten years	266,262
Mortgage backed securities	384,772
Total fixed maturities	$ 1,825,759

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