Reinsurance (Details) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2012	Dec. 31, 2011	Dec. 31, 2010
Reinsurance
Gross Amount	$ 696,721	$ 695,264	$ 702,930
Ceded to Other Companies	29,634	31,940	35,057
Assumed from Other Companies	3,440	3,796	4,805
Net Amount	670,527	667,120	672,678
Percentage of Amount Assumed to Net	0.50%	0.60%	0.70%
Life Insurance in Force [Member]
Reinsurance
Gross Amount	14,632,272	14,161,408	13,939,851
Ceded to Other Companies	3,070,951	2,836,731	2,548,774
Net Amount	11,561,321	11,324,677	11,391,077
Property and casualty segment [Member]
Reinsurance
Gross Amount	566,853	570,264	580,512
Ceded to Other Companies	23,954	26,520	29,492
Assumed from Other Companies	3,440	3,796	4,805
Net Amount	546,339	547,540	555,825
Percentage of Amount Assumed to Net	0.60%	0.70%	0.90%
Annuity [Member]
Reinsurance
Gross Amount	21,794	18,883	17,346
Net Amount	21,794	18,883	17,346
Life [Member]
Reinsurance
Gross Amount	108,074	106,117	105,072
Ceded to Other Companies	5,680	5,420	5,565
Net Amount	$ 102,394	$ 100,697	$ 99,507

Amount of premiums assumed from other companies.

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

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