Investments (Details 15) (USD $) In Thousands, unless otherwise specified	Jun. 30, 2013	Dec. 31, 2012
Financing Receivable Recorded Investment Aging
Total mortgage loans	$ 2,385,149	$ 2,312,167
Investment in mortgage loans
Financing Receivable Recorded Investment Aging
31-60 days past due	20,563	7,504
61-90 days past due	0	0
Greater than 90 days	7,930	16,886
Total past due	28,493	24,390
Current	2,356,656	2,287,777
Total mortgage loans	$ 2,385,149	$ 2,312,167

Financing receivables that are less than 60 days past due but more than 29 days past due.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 7A

-URI http://asc.fasb.org/extlink&oid=28368275&loc=SL6953401-111524

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Financing receivables that are less than 90 days past due but more than 59 days past due.

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- Definition

Financing receivables that are current.

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- Definition

Financing receivables that are equal to or greater than 90 days past due.

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- Definition

Recorded Investment in financing receivables that are past due at the balance sheet date.

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- Definition

Amount before allowance of commercial loans issued to businesses to acquire, develop, construct, improve, or refinance land or building. Includes deferred interest and fees, undisbursed portion of loan balance, unamortized costs and premiums and discounts from face amounts. Excludes loans covered under loss sharing agreements.

+ References

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

-Section 50

-Paragraph 3

-URI http://asc.fasb.org/extlink&oid=28368275&loc=d3e5066-111524

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

-Publisher SEC

-Name Regulation S-X (SX)

-Number 210

-Section 03

-Paragraph 7

-Subparagraph a

-Article 9

Reference 3: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

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-URI http://asc.fasb.org/extlink&oid=6876686&loc=d3e534808-122878

Reference 4: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 944

-SubTopic 210

-Section S99

-Paragraph 1

-Subparagraph (SX 210.7-03.1(c))

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