Percentage of PVFP Balance Net of Interest Accretion, before Effect of Unrealized Investment Gains or Losses, Estimated to be Amortized over Next Five Years (Detail)	12 Months Ended
Dec. 31, 2012
Finite-Lived Intangible Assets [Line Items]
2013	5.00%
2014	5.50%
2015	8.10%
2016	8.40%
2017	6.40%

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Estimated percentage of the ending balance of the present value of the future insurance profits asset acquired in the purchase of an insurance entity to be amortized in the fifth year after the balance sheet date.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Emerging Issues Task Force (EITF)

-Number 92-9

-LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy.

Reference 2: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 20

-Section S99

-Paragraph 2

-Subparagraph (3)

-URI http://asc.fasb.org/extlink&oid=6784649&loc=d3e569990-122904

+ Details

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- Definition

Estimated percentage of the ending balance of the present value of the future insurance profits asset acquired in the purchase of an insurance entity to be amortized in the fourth year after the balance sheet date.

+ References

+ Details

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- Definition

Estimated percentage of the ending balance of the present value of future profits asset acquired in the purchase of an insurance entity to be amortized in the first year after the balance sheet date.

+ References

+ Details

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- Definition

Estimated percentage of the ending balance of the present value of the future insurance profits asset acquired in the purchase of an insurance entity to be amortized in the third year after the balance sheet date.

+ References

+ Details

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- Definition

Estimated percentage of the ending balance of the present value of the future insurance profits asset acquired in the purchase of an insurance entity to be amortized in the second year after the balance sheet date.

+ References

+ Details

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