Contingencies and Other Matters (Details) (USD $)	9 Months Ended
	Sep. 30, 2013
Contingencies And Other Matters Details [Abstract]
Liabilities Required Indemnification Obligations Acquisitions and Dispositions	0
Market Value Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	$ 41,000,000
Indemnification Guarantee [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	284,000,000
Guarantee Type, Other [Member] | Retirement And Life Insurance Contracts [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Current Carrying Value	518,000,000
Separate Accounts Liability Sold Business Percent Reinsured	14.00%
Guarantee Type, Other [Member] | Variable Annuity [Member] | Guaranteed Minimum Income Benefit [Member]
Guarantee Obligations [Line Items]
Guarantee Obligations, Maximum Exposure, Undiscounted	856,000,000
Underlying mutual fund investment values for Guaranteed Minimum Income Benefits	$ 1,100,000,000