Certain Nontraditional Long-Duration Contracts (Guarantees Associated with Variable Annuity Contracts, by Guarantee Type) (Details) (variableannuity, USD $) In Thousands, unless otherwise specified	12 Months Ended
	Dec. 31, 2013		Dec. 31, 2012
Net Amount At Risk By Product And Guarantee [Line Items]
Average Period Remaining Until Expected Annuitization At Annuitization Accumulation	0 years 2 months 0 days		0 years 5 months 0 days
Return of net deposits
Net Amount At Risk By Product And Guarantee [Line Items]
Account value in the event of death	$ 40,828,166		$ 39,883,202
NetAmountAtRiskByProductAndGuaranteeNetAmountAtRiskInEventOfDeath	407,488		603,793
Average Attained Age of Contractholders In the Event of Death	64 years 0 months 0 days		63 years 0 months 0 days
Minimum return or contract value
Net Amount At Risk By Product And Guarantee [Line Items]
Account value in the event of death	8,446,938		8,293,324
NetAmountAtRiskByProductAndGuaranteeNetAmountAtRiskInEventOfDeath	916,094		1,242,583
Account value at annuitization or accumulation	40,678,507	[1]	39,685,368	[1]
NetAmountAtRiskByProductAndGuaranteeNetAmountAtRiskAtAnnuitization	$ 1,272,641	[1]	$ 2,147,087	[1]
Average Attained Age of Contractholders In the Event of Death	66 years 0 months 0 days		65 years 0 months 0 days
Average attained age of contractholders At Annuitization Accumulation	64 years 0 months 0 days		63 years 0 months 0 days

[1] Includes income and withdrawal benefits described herein