Investments (Narrative) (Details) (USD $) In Millions, unless otherwise specified	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2011
Gain (Loss) on Investments [Line Items]
Fixed maturities, fair value of hybrid securities	$ 18	$ 31
Investments, deposit with various states	80	85
Investments in fair value, deposit with various states	14,192	13,164
Impaired securities	7	13	12
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments	5	1
Fixed Maturities [Member]
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments	558	874
Number of securities total unrealized loss in an unrealized loss position for 12 months or more	40	4	20
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments	5	1	5
Equity Securities [Member]
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments	1,856	1,014
Number of securities total unrealized loss in an unrealized loss position for 12 months or more			2
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments	0	0
Equity Securities [Member] | Maximum [Member]
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Continuous Unrealized Loss Position, 12 Months or Longer, Aggregate Loss, Accumulated in Investments			1
Procter And Gamble Company, Exxon Mobile Corporation And Chevron Corporation [Member]
Gain (Loss) on Investments [Line Items]
Available-for-sale Securities, Gross Unrealized Gain, Accumulated in Investments	452
Three Primary Contributors
Gain (Loss) on Investments [Line Items]
Number of securities	5
On Deposit With Various States
Gain (Loss) on Investments [Line Items]
Investments in fair value, deposit with various states	$ 84	$ 93