Investments (All Other Net Unrealized Investment Gains and Losses in AOCI) (Details) (USD $)
In Thousands, unless otherwise specified
 12 Months Ended
Dec. 31, 2013
Dec. 31, 2012
Dec. 31, 2011
Balance $ 56,646 $ 267,461  
Other Net Unrealized Investment Gains and Losses [Member] | Accumulated Net Unrealized Investment Gain (Loss) Pre Tax [Member]
      
Balance 505,100 [1] 443,637 [1] 400,404 [1]
Net investment gains (losses) on investments arising during the period (343,964) [1] 90,693 [1] 128,890 [1]
Reclassification adjustment for (gains) losses included in net income (38,034) [1] (29,399) [1] (85,445) [1]
Reclassification adjustment for OTTI losses excluded from net income 51 [1],[2] 169 [1],[2] (212) [1],[2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs 0 [1] 0 [1] 0 [1]
Impact of net unrealized investment (gains) losses on policyholders' account balance 0 [1] 0 [1] 0 [1]
Balance 123,153 [1] 505,100 [1] 443,637 [1]
Other Net Unrealized Investment Gains and Losses [Member] | Deferred Costs Policy Acquisition And Sales Inducements And Valuation Of Business Acquired, Pre Tax [Member]
      
Balance (220,208) (179,520) (194,158)
Net investment gains (losses) on investments arising during the period 0 0 0
Reclassification adjustment for (gains) losses included in net income 0 0 0
Reclassification adjustment for OTTI losses excluded from net income 0 [2] 0 [2] 0 [2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs 177,178 (40,688) 14,638
Impact of net unrealized investment (gains) losses on policyholders' account balance 0 0 0
Balance (43,030) (220,208) (179,520)
Other Net Unrealized Investment Gains and Losses [Member] | Policyholders Account Balances Pre Tax [Member]
      
Balance 125,833 75,345 92,690
Net investment gains (losses) on investments arising during the period 0 0 0
Reclassification adjustment for (gains) losses included in net income 0 0 0
Reclassification adjustment for OTTI losses excluded from net income 0 [2] 0 [2] 0 [2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs 0 0 0
Impact of net unrealized investment (gains) losses on policyholders' account balance (122,540) 50,488 (17,345)
Balance 3,293 125,833 75,345
Other Net Unrealized Investment Gains and Losses [Member] | Deferred Income Tax Liability Benefit [Member]
      
Balance (143,646) (118,533) (104,367)
Net investment gains (losses) on investments arising during the period 120,388 (31,738) (45,090)
Reclassification adjustment for (gains) losses included in net income 13,312 10,290 29,905
Reclassification adjustment for OTTI losses excluded from net income (18) [2] (59) [2] 73 [2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs (62,012) 14,065 (5,124)
Impact of net unrealized investment (gains) losses on policyholders' account balance 42,889 (17,671) 6,070
Balance (29,087) (143,646) (118,533)
Other Net Unrealized Investment Gains and Losses [Member] | Accumulated Net Unrealized Investment Gain (Loss) [Member]
      
Balance 267,079 220,929 194,569
Net investment gains (losses) on investments arising during the period (223,576) 58,955 83,800
Reclassification adjustment for (gains) losses included in net income (24,722) (19,109) (55,540)
Reclassification adjustment for OTTI losses excluded from net income 33 [2] 110 [2] (139) [2]
Impact of net unrealized investment (gains) losses on deferred policy acquisition costs 115,166 (26,623) 9,514
Impact of net unrealized investment (gains) losses on policyholders' account balance (79,651) 32,817 (11,275)
Balance $ 54,329 $ 267,079 $ 220,929
[1] _____________ Includes cash flow hedges. See Note 11 for information on cash flow hedges.
[2] Represents “transfers out” related to the portion of OTTI losses recognized during the period that were not recognized in earnings for securities with no prior OTTI loss. Balances are net of reinsurance.