Amortized cost of investment in fixed maturities rated below investment grade

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- Definition

Fair Value Of Investment In Fixed Maturities Rated Below Investment Grade

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- Definition

Investment in low-income housing tax entities, carrying value.

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- Definition

Letters Of Credit Facility Limit

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- Definition

Number of guarantees

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- Definition

Par value of investment in fixed maturities rated below investment grade

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No definition available.

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- Definition

Percentage of invested assets rated below investment grade

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No definition available.

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- Definition

Proportion Of State And Municipal Government Securities At Fair Value Invested In Selected States

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- Definition

Proportion Of State And Municipal Governments Securities At Fair Value In Investment Portfolio

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- Definition

Purchase Commitments Under Low-Income Housing Program

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- Definition

Recorded unconditional purchase obligation thereafter

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- Definition

Reinsurance assumed ratio on premium income

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- Definition

Retention limits per life for ordinary life insurance

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- Definition

State and municipal government securities at fair value invested by state.

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- Definition

Ratio of insurance contracts that are subject to reinsurance participation to all contracts in force.

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No definition available.

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- Definition

Maximum potential amount of future payments (undiscounted) the guarantor could be required to make under the guarantee or each group of similar guarantees before reduction for potential recoveries under recourse or collateralization provisions.

+ References

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

-Publisher FASB

-Name FASB Interpretation (FIN)

-Number 45

-Paragraph 13

-Subparagraph b

-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.

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This item represents a non-contingent liability for the fair value of an obligation to stand ready to perform over the term of a guaranty issued in the event that specified triggering events or conditions occur.

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-Name Accounting Standards Codification

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-Paragraph 3

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- Definition

The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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No definition available.

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- Definition

Life insurance assumed from another insurer divided by gross life insurance in force.

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-Name Regulation S-X (SX)

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Amount of required minimum rental payments maturing in the next fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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

-Publisher FASB

-Name Statement of Financial Accounting Standard (FAS)

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-Subparagraph b(i)

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-SubTopic 20

-Section 50

-Paragraph 2

-Subparagraph (a)

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Amount of required minimum rental payments maturing in the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the forth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the third fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing in the second fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Amount of required minimum rental payments maturing after the fifth fiscal year following the latest fiscal year for operating leases having an initial or remaining non-cancelable letter-terms in excess of one year.

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Rental expense for the reporting period incurred under operating leases, including minimum and any contingent rent expense, net of related sublease income.

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-Name Accounting Standards Codification

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- Definition

Ratio of premium income to reinsurance.

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No definition available.

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Amount of the recorded unconditional purchase obligation maturing in the second fiscal year following the latest fiscal year.

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-Publisher FASB

-Name Accounting Standards Codification

-Topic 440

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Amount of the recorded unconditional purchase obligation maturing in the third fiscal year following the latest fiscal year.

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Amount of the recorded unconditional purchase obligation maturing in the next fiscal year following the latest fiscal year.

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Commitments and Contingencies - Additional Information (Detail) (USD $)	12 Months Ended
	Dec. 31, 2012 Contract	Dec. 31, 2011	Dec. 31, 2010
Commitment And Contingencies [Line Items]
Retention limits per life	$ 2,000,000
Percentage of insurance ceded on total life insurance in force	0.50%
Percentage of insurance ceded on premium income	0.30%
Life reinsurance assumed rate on life insurance in force	2.70%
Reinsurance assumed ratio on premium income	1.10%
Rental expense for operating leases	3,600,000	4,800,000	4,900,000
Future minimum rental commitments in 2013	3,400,000
Future minimum rental commitments in 2014	2,900,000
Future minimum rental commitments in 2015	2,900,000
Future minimum rental commitments in 2016	1,600,000
Future minimum rental commitments in 2017	1,100,000
Future minimum rental commitments in aggregate	13,500,000
Investment in low-income housing interests	285,000,000	293,000,000
Obligations under commitments	67,000,000
Obligations under commitments due in 2013	47,000,000
Obligations under commitments due in 2014	16,000,000
Obligations under commitments due in 2015	1,000,000
Recorded unconditional purchase obligation thereafter	3,000,000
Securities of state and municipal governments	10.00%
Proportion of state and municipal government securities at fair value invested in selected states	5.00%
Par value of investment in fixed maturities rated below investment grade	694,000,000
Amortized cost of investment in fixed maturities rated below investment grade	585,000,000
Fair value of investment in fixed maturities rated below investment grade	547,000,000
Percentage of invested assets rated below investment grade	4.00%
Number of guarantee agreements in place	3
Guaranty liability	0
Maximum daily amount letters of credit facility	250,000,000		250,000,000
Letters of credit facility outstanding	198,000,000	198,000,000
Undiscounted payments under leases	$ 7,000,000
Texas
Commitment And Contingencies [Line Items]
State and municipal government securities at fair value invested by state	0.31
Ohio
Commitment And Contingencies [Line Items]
State and municipal government securities at fair value invested by state	0.08
Washington
Commitment And Contingencies [Line Items]
State and municipal government securities at fair value invested by state	0.07
Illinois
Commitment And Contingencies [Line Items]
State and municipal government securities at fair value invested by state	0.05
Alabama
Commitment And Contingencies [Line Items]
State and municipal government securities at fair value invested by state	0.05