v2.4.0.6

Increase or (Decrease) in Carrying Value of Investment in Life Insurance Policies (Detail) (USD $) In Thousands, unless otherwise specified | 9 Months Ended | 12 Months Ended
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Sep. 30, 2012 | Dec. 31, 2011
Disclosure Increase Or Decrease In Carrying Value Of Investment In Life Insurance Policies [Abstract] |  |
Life expectancy Plus 4 Months | $ (25,386) | $ (18,778)
Life expectancy Minus 4 Months | 28,250 | 20,785
Discount Plus 1% | (17,167) | (13,802)
Discount Minus 1% | $ 20,030 | $ 15,804

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