Insurance (Guarantees Related to Annuity Contracts) (Details) (USD $) In Millions, unless otherwise specified	3 Months Ended	12 Months Ended
	Mar. 31, 2014	Dec. 31, 2013
Variable Annuity Guarantees [Member] | Guaranteed Death Benefits [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Account value	$ 200,796	$ 201,395
Separate account value in event of death	164,767	164,500
Net amount at risk in event of death	4,336	4,203
Average attained age of contractholders	64 years	63 years
Variable Annuity Guarantees [Member] | Guaranteed Annuitization Benefits [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Account value	100,746	100,527
Separate account value at annuitization	96,749	96,459
Net amount at risk at annuitization	1,305	1,219
Average attained age of contractholders	64 years	63 years
Two Tier Annuities [Member] | Guaranteed Annuitization Benefits [Member]
Net Amount at Risk by Product and Guarantee [Line Items]
Account value	1,021	880
Net amount at risk at annuitization	$ 313	$ 234
Average attained age of contractholders	49 years	50 years