SCHEDULE IV - Reinsurance (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reinsurance premiums
Gross amount	$ 84,815	$ 73,567	$ 25,532
Ceded to other companies	155,010	141,539	180,426
Assumed from other companies	4,556,134	4,715,726	4,931,365
Net amount	4,485,939	4,647,754	4,776,471
Percentage of amount assumed to net	102.00%	101.00%	103.00%
[LifeInsuranceInForceMember]
Life reinsurance in force
Gross amount	0	0	0
Ceded to other companies	1,782,549	1,673,196	1,726,050
Assumed from other companies	214,006,823	199,347,294	192,669,971
Net amount	212,224,274	197,674,098	190,943,921
Percentage of amount assumed to net	101.00%	101.00%	101.00%
[LifeInsuranceSegmentMember]
Reinsurance premiums
Gross amount	0	0	0
Ceded to other companies	5,400	3,470	5,118
Assumed from other companies	780,279	774,383	729,007
Net amount	774,879	770,913	723,889
Percentage of amount assumed to net	101.00%	100.00%	101.00%
[AccidentAndHealthInsuranceSegmentMember]
Reinsurance premiums
Gross amount	0	0	0
Ceded to other companies	0	0	0
Assumed from other companies	19,719	21,235	19,676
Net amount	19,719	21,235	19,676
Percentage of amount assumed to net	100.00%	100.00%	100.00%
[PropertyLiabilityAndCasualtyInsuranceSegmentMember]
Reinsurance premiums
Gross amount	84,815	73,567	25,532
Ceded to other companies	149,610	138,069	175,308
Assumed from other companies	3,756,136	3,920,108	4,182,682
Net amount	$ 3,691,341	$ 3,855,606	$ 4,032,906
Percentage of amount assumed to net	102.00%	102.00%	104.00%

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Represents the gross amount of death benefits (face amount of policies) assumed from other companies under reinsurance contracts in force as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the gross amount of death benefits (face amount of policies) ceded to other companies under reinsurance contracts in force as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the gross amount of death benefits (face amount of policies) under reinsurance contracts in force as of the balance sheet date.

+ References

No definition available.

+ Details

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- Definition

Represents the net amount of death benefits (face amount of policies) under reinsurance contracts in force as of the balance sheet date. The net amount is calculated as the gross amount, less amounts ceded to other companies, plus amounts assumed from other companies.

+ References

No definition available.

+ Details

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- Definition

The ratio of face amount of life reinsurance policies assumed to the net amount of of life reinsurance policies in force as of the balance sheet date..

+ References

No definition available.

+ Details

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- Definition

Amount of premiums assumed from other companies.

+ References

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 17

-Article 12

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 235

-Section S99

-Paragraph 2

-Subparagraph (SX 210.12-17)

-URI http://asc.fasb.org/extlink&oid=6588446&loc=d3e574992-122915

+ Details

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- Definition

Amount of premiums ceded to other companies.

+ References

+ Details

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- Definition

Gross amount of premium revenue.

+ References

+ Details

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- Definition

Net amount of gross premiums, less premiums ceded to other companies, plus premiums assumed from other companies; which represents the net amount of premium revenue on the income statement.

+ References

+ Details

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- Definition

Percentage of amount of premiums assumed from other companies to net amount of premiums.

+ References

+ Details

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