Investments (Details 16) (USD $)	Dec. 31, 2012	Dec. 31, 2011
Mortgage Loans [Abstract]
Financing Receivable, Individually Evaluated for Impairment	$ 39,956,000	$ 60,904,000
Financing Receivable, Collectively Evaluated for Impairment	2,272,211,000	942,620,000
Loans Receivable, Gross, Commercial, Real Estate	2,312,167,000	1,003,524,000
Valuation Allowances [Abstract]
Financing Receivable, Allowance for Credit Losses, Individually Evaluated for Impairment	6,980,000	8,188,000
Financing Receivable, Allowance for Credit Losses, Collectively Evaluated for Impairment	4,600,000	3,605,000
Financing Receivable Allowance For Credit Losses Total	11,580,000	11,793,000
Mortgage Loans Net Of Valuation Allowance [Abstract]
Mortgage loans on real estate	$ 2,300,587,000	$ 991,731,000

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The valuation allowance for financing receivables that are expected to be uncollectible that were collectively evaluated for impairment.

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-Publisher FASB

-Name Accounting Standards Codification

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The valuation allowance for financing receivables that are expected to be uncollectible that were individually evaluated for impairment.

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The balance of financing receivables that were collectively evaluated for impairment.

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The balance of financing receivables that were individually evaluated for impairment.

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Reflects the sum of the gross carrying amounts of unpaid loans issued to businesses to acquire, develop, construct, improve, or refinance land or a building. Includes [but is not limited to] commercial mortgage loans, which are secured by a [legal] security interest in real property [commercial building or business real property] which thereby serves as collateral securing repayment of the loan; and construction financing, which is an obligation generally in the form of a [promissory] note, used for the funding of construction projects.

+ References

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

-Publisher AICPA

-Name Audit and Accounting Guide (AAG)

-Number AAG-DEP

-Chapter 8

-Paragraph 51, 52, 53

-IssueDate 2006-05-01

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-Name Statement of Financial Accounting Standard (FAS)

-Number 60

-Paragraph 47

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-Publisher SEC

-Name Regulation S-X (SX)

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The balance represents the amount of loans that are secured by real estate mortgages, offset by the reserve to cover probable credit losses on the loan portfolio.

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