Investment Income and Gains and Losses - Net Investment Income (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	$ 1,200	$ 1,184	$ 1,183
Less: investment expenses	36	40	37
Net investment income	1,164	1,144	1,146
Net investment income for separate accounts	232	181	207
Fixed Maturities [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	823	843	817
Equity securities [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	6	4	6
Commercial Mortgage Loans [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	174	192	218
Policy Loans [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	74	74	86
Real Estate [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	(1)	(2)	(2)
Other Long Term Investments [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	102	59	48
Short-term investments and cash [Member]
Schedule Of Investment Income Reported Amounts By Category [Line Items]
Gross investment income	$ 22	$ 14	$ 10