Schedule of Key Assumptions Used In Calculation Reserve for Life-Contingent Contract Benefits (Detail)	12 Months Ended
Dec. 31, 2012
Traditional life insurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Mortality	Actual company experience plus loading
Interest rate discription	Interest rate assumptions range from 4.0% to 8.0%
Interest rate, low end	4.00%
Interest rate, high end	8.00%
Estimation method	Net level premium reserve method using the Company's withdrawal experience rates; includes reserves for unpaid claims
Immediate fixed annuities
Liability for Future Policy Benefit, by Product Segment [Line Items]
Mortality	1983 individual annuity mortality table with interna modifications; 198 individual annuity mortality table; Annuity 2000 mortality table with internal modifications
Estimation method	Present value of expected future benefits based on historical experience
Interest rate discription	Interest rate assumptions range from 1.3% to 8.8%
Interest rate, low end	1.30%
Interest rate, high end	8.80%
Accident And Health Insurance
Liability for Future Policy Benefit, by Product Segment [Line Items]
Mortality	Actual company experience plus loading
Estimation method	Unearned premium; additional contract reserves for mortality risk and unpaid claims
Interest rate discription	Interest rate assumptions range from 4.0% to 5.3%
Interest rate, low end	4.00%
Interest rate, high end	5.30%
Guaranteed death benefits
Liability for Future Policy Benefit, by Product Segment [Line Items]
Mortality	Annuity 2000 mortality table with internal modifications
Estimation method	Projected benefit ratio applied to cumulative assessments
Interest rate discription	Interest rate assumptions range from 4.0% to 5.8%
Interest rate, low end	4.00%
Interest rate, high end	5.80%

Accident And Health Insurance, Interest Rate Assumptions

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Accident And Health Insurance Interest Rate, High End

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Accident And Health Insurance Interest Rate, Low End

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Other Contracts, Interest Rate Assumptions

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Other Contracts, Interest Rate Assumptions, High End

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Other Contracts, Interest Rate Assumptions, Low End

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Other Immediate Fixed Annuities, Interest Rate Assumptions

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Other Immediate Fixed Annuities, Interest Rate Assumptions, High End

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Other Immediate Fixed Annuities, Interest Rate Assumptions, Low End

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Methodology and assumptions for accrued obligation to policyholders that relates to insured events, and can be viewed as either (a) the present value of future benefits to be paid to or on behalf of policyholders and expenses less the present value of future net premiums payable under the insurance contracts or (b) the accumulated amount of net premiums already collected less the accumulated amount of benefits and expenses already paid to or on behalf of policyholders.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

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-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 13

-Subparagraph b

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Relevant mortality and surrender rate assumptions that are an integral part of the methodology used in calculating the reserve for future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and cost of settling insured claims and cost incurred in the claim settlement process.

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Relevant interest rate assumption for traditional life contracts that is an integral part of the methodology used in calculating the future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and costs of settling insured claims and costs incurred in the claims settlement process for traditional life.

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Maximum interest rate for traditional life contracts in the range of interest rates used to calculate future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and costs of settling insured claims and costs incurred in the claims settlement process of traditional life.

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Minimum interest rate for traditional life contracts in the range of interest rates used to calculate future benefits to be paid to or on behalf of policyholders and related expenses less the present value of future net premiums using assumptions such as estimates of expected investment yields, mortality, morbidity, terminations and expenses, applicable at the time the insurance contracts are made and costs of settling insured claims and costs incurred in the claims settlement process of traditional life.

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-Name Accounting Standards Codification

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