Investments (Details 11) - USD ($)	12 Months Ended
Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Investments
Maximum exposure to loss related to VIE's	$ 2,924,000
Unfunded commitments	$ 18,000
Minimum percentage of securities received as collateral	102.00%
Collateral held under securities lending	$ 0	$ 42,941,000
Liability to the borrower for collateral	0	42,941,000
CPI CAPs
Investments
Derivative assets included in other assets	398,000	692,000
Loss on derivatives included in earnings	294,000	1,324,000	$ 3,094,000
Fixed maturity securities
Investments
Fixed maturity securities on deposit with various governmental authorities	11,248,000	11,592,000
Investment purchases commitments
Investments
Commercial mortgage loans	1,750,000
Real estate joint ventures	18,000
Commercial mortgage loans
Investments
Decrease in loan valuation allowance	390,000	583,000
Commercial mortgage loans	$ 421,643,000	$ 501,278,000

Line items represent reporting concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Carrying amount of cash and investment securities on deposit with state regulatory authorities in connection with capital requirements.

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Amount of direct write-downs of financing receivables charged against the allowance.

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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.

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