Variable Annuity and Insurance Guarantees (IUL Secondary Guarantees) (Details) - UL secondary guarantees [Member] - USD ($) $ in Millions	6 Months Ended	12 Months Ended
	Jun. 30, 2016	Dec. 31, 2015
Insurance Guarantees by Benefit Type
Net amount at risk	$ 6,301	$ 6,601
Weighted average attained age	64 years	63 years