Insurance (Guarantees Related to Universal and Variable Life Contracts) (Details) (Universal And Variable Life Contracts [Member], USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013
Secondary Guarantees
Net Amount at Risk by Product and Guarantee [Line Items]
Account value (general and separate account)	$ 8,213	$ 7,871
Net amount at risk	78,758	81,888
Average attained age of policyholders	54 years	53 years
Paid-Up Guarantees
Net Amount at Risk by Product and Guarantee [Line Items]
Account value (general and separate account)	1,091	1,125
Net amount at risk	$ 8,164	$ 8,701
Average attained age of policyholders	60 years	59 years