Fair Value of Assets and Liabilities (Financial Instruments where Carrying Amounts and Fair Values May Differ) (Details) (USD $)
In Thousands, unless otherwise specified
Dec. 31, 2013
Dec. 31, 2012
Assets:    
Policy loans $ 1,086,772 $ 1,079,714
Other Long-Term Investments 226,704 284,489
Accrued investment income 89,465 90,653
Liabilities:    
Cash collateral for loaned securities 84,867 48,068
Short-term debt 274,900 272,000
Long-term debt 1,592,000 1,511,000
Fair Value, Inputs, Level 1 [Member]
    
Assets:    
Commercial mortgage and other loans 0  
Policy loans 0  
Cash 45,317  
Accrued investment income 0  
Other assets 0  
Liabilities:    
Investment contracts- policyholders' account balances 0  
Cash collateral for loaned securities 0  
Long-term debt 0  
Other liabilities 0  
Fair Value, Inputs, Level 2 [Member]
    
Assets:    
Commercial mortgage and other loans 7,827  
Policy loans 0  
Accrued investment income 89,465  
Other assets 34,060  
Liabilities:    
Investment contracts- policyholders' account balances 851,607  
Cash collateral for loaned securities 84,867  
Short-term debt 275,268  
Long-term debt 1,644,827  
Other liabilities 270,339  
Fair Value, Inputs, Level 3 [Member]
    
Assets:    
Commercial mortgage and other loans 1,604,247  
Policy loans 1,086,772  
Accrued investment income 0  
Other assets 0  
Liabilities:    
Investment contracts- policyholders' account balances 40,451  
Cash collateral for loaned securities 0  
Short-term debt 0  
Long-term debt 0  
Other liabilities 0  
Carrying (Reported) Amount, Fair Value Disclosure [Member]
    
Assets:    
Commercial mortgage and other loans 1,532,165 [1] 1,463,977
Policy loans 1,086,772 [1] 1,079,714
Other Long-Term Investments 4,268 [1] 2,119
Cash 101,456 [1] 94,410
Accrued investment income 89,465 [1] 90,653
Receivables From Parents And Affiliates 87,481 [1] (3,751)
Other assets 34,060 [1] 32,176
Total Assets Financial Instruments Not Carried At Fair Value 2,935,667 [1] 2,759,298
Liabilities:    
Investment contracts- policyholders' account balances 901,860 [1] 796,816
Cash collateral for loaned securities 84,867 [1] 48,068
Short-term debt 274,900 [1] 272,000
Long-term debt 1,592,000 [1] 1,511,000
Payables To Parent And Affiliates 45,649 [1] 6,694
Other liabilities 270,339 [1] 224,751
Total Financial Instrument Liabilities Not Carried At Fair Value 3,169,615 [1] 2,859,329
Estimate of Fair Value, Fair Value Disclosure [Member]
    
Assets:    
Commercial mortgage and other loans 1,612,074 1,616,804
Policy loans 1,086,772 1,455,412
Other Long-Term Investments 4,751 2,491
Cash 101,456 94,410
Accrued investment income 89,465 90,653
Receivables From Parents And Affiliates 87,849 (3,146)
Other assets 34,060 32,782
Total Assets Financial Instruments Not Carried At Fair Value 3,016,427 3,289,406
Liabilities:    
Investment contracts- policyholders' account balances 892,058 793,280
Cash collateral for loaned securities 84,867 48,068
Short-term debt 275,268 272,981
Long-term debt 1,644,827 1,563,185
Payables To Parent And Affiliates 45,649 6,694
Other liabilities 270,339 224,751
Total Financial Instrument Liabilities Not Carried At Fair Value 3,213,008 2,908,959
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 1 [Member]
    
Assets:    
Other Long-Term Investments 0  
Receivables From Parents And Affiliates 0  
Total Assets Financial Instruments Not Carried At Fair Value 45,317  
Liabilities:    
Short-term debt 0  
Payables To Parent And Affiliates 0  
Total Financial Instrument Liabilities Not Carried At Fair Value 0  
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 2 [Member]
    
Assets:    
Other Long-Term Investments 0  
Cash 56,139  
Receivables From Parents And Affiliates 87,849  
Total Assets Financial Instruments Not Carried At Fair Value 275,340  
Liabilities:    
Payables To Parent And Affiliates 45,649  
Total Financial Instrument Liabilities Not Carried At Fair Value 3,172,557  
Estimate of Fair Value, Fair Value Disclosure [Member] | Fair Value, Inputs, Level 3 [Member]
    
Assets:    
Other Long-Term Investments 4,751  
Cash 0  
Receivables From Parents And Affiliates 0  
Total Assets Financial Instruments Not Carried At Fair Value 2,695,770  
Liabilities:    
Payables To Parent And Affiliates 0  
Total Financial Instrument Liabilities Not Carried At Fair Value $ 40,451  
[1] Carrying values presented herein differ from those in the Company’s Consolidated Statement of Financial Position because certain items within the respective financial statement captions are not considered financial instruments or out of scope under authoritative guidance relating to disclosures of the fair value of financial instruments. Financial statement captions excluded from the above table are not considered financial instruments.