Investments (Credit Quality Indicators For Commercial Mortgage Loans) (Details) - USD ($) $ in Thousands	Dec. 31, 2015	Dec. 31, 2014
Financing Receivable, Recorded Investment [Line Items]
Gross commercial mortgage loans	$ 1,153,838	$ 1,276,015
% of Gross Mortgage Loans	100.00%	100.00%
Debt-Service Coverage Ratio	1.98	1.94
Less valuation allowance	$ (2,582)	$ (3,399)
Net commercial mortgage loans	1,151,256	1,272,616
70% and less
Financing Receivable, Recorded Investment [Line Items]
Gross commercial mortgage loans	$ 1,101,572	$ 1,168,454
% of Gross Mortgage Loans	95.50%	91.60%
Debt-Service Coverage Ratio	2.01	2.01
71 – 80%
Financing Receivable, Recorded Investment [Line Items]
Gross commercial mortgage loans	$ 39,080	$ 73,762
% of Gross Mortgage Loans	3.40%	5.80%
Debt-Service Coverage Ratio	1.19	1.26
81 – 95%
Financing Receivable, Recorded Investment [Line Items]
Gross commercial mortgage loans	$ 8,370	$ 27,268
% of Gross Mortgage Loans	0.70%	2.10%
Debt-Service Coverage Ratio	1.05	1.04
Greater than 95%
Financing Receivable, Recorded Investment [Line Items]
Gross commercial mortgage loans	$ 4,816	$ 6,531
% of Gross Mortgage Loans	0.40%	0.50%
Debt-Service Coverage Ratio	3.52	0.43

Credit Quality Percentage for Gross Commercial Mortgage Loans

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- Definition

Debt-Service Coverage Ratios for Commercial Mortgage Loans

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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
-Publisher FASB
-Name Accounting Standards Codification
-Topic 310
-SubTopic 40
-Section 50
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-Publisher SEC
-Name Staff Accounting Bulletin (SAB)
-Number Topic 6
-Section L
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Reference 7: http://www.xbrl.org/2003/role/presentationRef
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-Name Regulation S-X (SX)
-Number 210
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-Paragraph 7
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- Definition

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.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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