Investments (Details 10) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Commercial mortgage loans
Net commercial mortgage loans	499,814	562,368
70% and less \| Maximum
Commercial mortgage loans
Loan-to-value percentage	70.00%	70.00%
71 - 80% \| Minimum
Commercial mortgage loans
Loan-to-value percentage	71.00%	71.00%
71 - 80% \| Maximum
Commercial mortgage loans
Loan-to-value percentage	80.00%	80.00%
81 - 95% \| Minimum
Commercial mortgage loans
Loan-to-value percentage	81.00%	81.00%
81 - 95% \| Maximum
Commercial mortgage loans
Loan-to-value percentage	95.00%	95.00%
Greater than 95% \| Minimum
Commercial mortgage loans
Loan-to-value percentage	95.00%	95.00%
Commercial mortgage loans
Commercial mortgage loans
Commercial mortgage loans	501,278	564,415
Less valuation allowance	(1,464)	(2,047)
Net commercial mortgage loans	499,814	562,368
% of Gross Mortgage Loans (as a percent)	100.00%	100.00%
Debt-Service Coverage Ratio	1.90	2.01
Commercial mortgage loans \| Minimum
Commercial mortgage loans
Commercial mortgage loans	77	22
Commercial mortgage loans \| Maximum
Commercial mortgage loans
Commercial mortgage loans	12,251	12,500
Commercial mortgage loans \| 70% and less
Commercial mortgage loans
Commercial mortgage loans	447,941	497,411
% of Gross Mortgage Loans (as a percent)	89.40%	88.20%
Debt-Service Coverage Ratio	1.99	2.08
Commercial mortgage loans \| 71 - 80%
Commercial mortgage loans
Commercial mortgage loans	40,651	41,943
% of Gross Mortgage Loans (as a percent)	8.10%	7.40%
Debt-Service Coverage Ratio	1.28	1.60
Commercial mortgage loans \| 81 - 95%
Commercial mortgage loans
Commercial mortgage loans	6,155	18,687
% of Gross Mortgage Loans (as a percent)	1.20%	3.30%
Debt-Service Coverage Ratio	0.99	1.35
Commercial mortgage loans \| Greater than 95%
Commercial mortgage loans
Commercial mortgage loans	6,531	6,374
% of Gross Mortgage Loans (as a percent)	1.30%	1.10%
Debt-Service Coverage Ratio	0.43	0.85
Commercial mortgage loans \| Investment portfolio \| Geographic concentration risk \| California, New York and Utah
Commercial mortgage loans
Concentration percentage	39.00%

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For an entity that discloses a concentration risk in relation to quantitative amount, which serves as the "benchmark" (or denominator) in the equation, this concept represents the concentration percentage derived from the division.

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- Definition

The allowance for commercial loan and lease losses represents the reserve to cover probable credit losses related to specifically identified commercial loans and leases, as well as probable credit losses inherent in the remainder of the commercial loan portfolio as of the balance sheet date. For banks, include currently required allocated transfer risk reserves. Include carryover of or adjustments to the allowance for commercial loan losses in connection with business combinations determined to be appropriate.

+ References

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

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Amount before allowance of mortgage loans on existing 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

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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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- Definition

Represents percentage of classified loans to total gross commercial mortgage loans.

+ References

No definition available.

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Represents the ratio of cash available for debt servicing of interest, principal and lease payments for commercial mortgage loans.

+ References

No definition available.

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Represents the ratio of a loan underwritten to a value of an asset purchased.

+ References

No definition available.

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