Nature of Operations, Basis of Presentation and Summary of Significant Accounting Policies (Details) item in Millions, $ in Millions	12 Months Ended
	Dec. 31, 2015 USD ($) item	Dec. 31, 2014 USD ($)	Dec. 31, 2013 USD ($)
Nature Of Operations And Basis Of Presentation [Abstract]
Grace Period Expiration (In Days)	10 days
Loans Reported As Delinquent In Days	60 days
Period In Which Loans No Longer Accrue Interest In Days	90 days
Estimated Contract Life UL Policies, Low End (In Years)	30 years
Estimated Contract Life UL Policies, High End (In Years)	40 years
Estimated Contract Life VUL Policies, Low End (In Years)	30 years
Estimated Contract Life VUL Policies, High End (In Years)	40 years
Estimated Contract Life Fixed and Variable Deferred Annuities, Low End (In Years)	15 years
Estimated Contract Life Fixed and Variable Deferred Annuities, High End (In Years)	30 years
Front End Load Annuity Products Assumed Life (In Years)	25 years
Max Of Amortization Period That Generally Results From Expected Premium-Paying Period (in years)	30 years
Useful life of sales force intangible assets (in years)	25 years
Number Of Scenarios Used Per Policy To Value A Block Of Guarantees	100
Total Scenarios To Value GLB liability | item	49
Investment yield assumptions for traditional direct individual life reserves, low end	2.25%
Investment yield assumptions for traditional direct individual life reserves, high end	7.75%
Investment yield assumptions for immediate and deferred paid-up annuities, low end	1.50%
Investment yield assumptions for immediate and deferred paid-up annuities, high end	13.50%
Participating policies as a percentage of the face amount of insurance in force	1.00%	1.00%
Dividend expenses | $	$ 67	$ 64	$ 62
No. of years in which deferred gain from reinsurance transaction is recognized as income	15 years
Interest crediting rate, low end	1.00%	1.00%	1.00%
Interest crediting rate, high end	10.00%	10.00%	10.00%