Consolidated Reinsurance (Narrative) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Consolidated Reinsurance
Reinsurance ceded	$ 916	$ 1,127	$ 1,063
Reinsurance assumed	13	81	296
Assumed Premiums, Life Insurance in Force	9,006	7,006	94,863
Ceded Premiums, Life Insurance in Force	194,032	450,000	466,406
Affiliated Entity [Member]
Consolidated Reinsurance
Assumed Premiums, Life Insurance in Force	9,000	7,000	86,400
Ceded Premiums, Life Insurance in Force	17,100	266,300	278,400
Life insurance (1)
Consolidated Reinsurance
Reinsurance ceded	689	909	824
Reinsurance assumed	13	67	84
Life insurance (1) | Affiliated Entity [Member]
Consolidated Reinsurance
Reinsurance ceded	537	766	687
Reinsurance assumed	$ 13	$ 35	$ 227