SOI Mortgage provision allowance rollforward (Details 4) (USD $) In Thousands, unless otherwise specified	12 Months Ended
Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Activity in the allowance for commercial mortgage loans credit losses
Beginning balance	$ 2,890	$ 2,890	$ 21,130
Provision increases	0us-gaap_ProvisionForLoanAndLeaseLosses	273us-gaap_ProvisionForLoanAndLeaseLosses	1,067us-gaap_ProvisionForLoanAndLeaseLosses
Charge-off	0	(273)	(992)
Recovery	0	0	(75)
Provision decreases	0	0	(18,240)
Ending balance	2,890	2,890	2,890
Allowance ending balance by basis of impairment method:
Collectively evaluated for impairment	2,890	2,890	2,890
Recorded investment balance in the mortgage loan portfolio, gross of allowance, by basis of impairment method:
Recorded investment balance in the mortgage loan portfolio, gross of allowance, by basis of impairment method	3,366,460	3,137,145	2,884,648
Individually evaluated for impairment	12,986	13,906	14,970
Collectively evaluated for impairment	$ 3,353,474	$ 3,123,239	$ 2,869,678

Amount of increase (decrease) of allowance reserve for credit loss.

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

-Publisher FASB

-Name Accounting Standards Codification

-Topic 310

-SubTopic 10

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

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The reserve to cover probable credit losses related to specifically identified fixed maturity real estate loans as well as probable credit losses inherent in the remainder of that loan portfolio.

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

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Amount of loans and leases that have been written off from both loan receivables and allowance reserve for credit loss.

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Amount of recovery of loans and lease receivables which had previously been fully or partially written-off as bad debts.

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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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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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Amount before allowance and after deduction of deferred interest and fees, unamortized costs and premiums and discounts from face amounts, of loans and leases held in portfolio, including but not limited to, commercial and consumer loans. Excludes loans and leases covered under loss sharing agreements.

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Amount of expense related to estimated loss from loan and lease transactions.

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