Certain Nontraditional Long-Duration Contracts (Account Balances of Variable Annuity Contracts with Guarantees Invested in General and Separate Account Investment Options) (Details) (USD $)	Dec. 31, 2013	Dec. 31, 2012
Net Amount At Risk By Product And Guarantee [Line Items]
NetAmountAtRiskByProductAndGuaranteeSeparateAccountValue	$ 46,347,647,000	$ 44,344,884,000
variableannuity
Net Amount At Risk By Product And Guarantee [Line Items]
netamountatriskbyproductandguaranteegeneralaccountvalue	2,900,000,000	3,800,000,000
variableannuity | EquityFundsMember
Net Amount At Risk By Product And Guarantee [Line Items]
NetAmountAtRiskByProductAndGuaranteeSeparateAccountValue	28,992,157,000	25,813,087,000
variableannuity | BondFundsMember [Member]
Net Amount At Risk By Product And Guarantee [Line Items]
NetAmountAtRiskByProductAndGuaranteeSeparateAccountValue	14,924,698,000	15,189,565,000
variableannuity | MoneyMarketFundsMember
Net Amount At Risk By Product And Guarantee [Line Items]
NetAmountAtRiskByProductAndGuaranteeSeparateAccountValue	$ 2,430,792,000	$ 3,342,232,000