Reinsurance (Effects of Reinsurance on Balance Sheet) (Details) - USD ($) $ in Millions	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014
Assets
Premiums and Other Receivables, Net	$ 26,081	$ 22,702
Deferred Policy Acquisition Costs and Value of Business Acquired	24,798	24,130	$ 24,442
Total assets	50,879	46,832
Liabilities
Future policy benefits (includes $0 and $716, respectively, relating to variable interest entities)	199,971	191,879
Policyholder account balances	210,235	202,722	$ 209,294
Other policy-related balances (includes $0 and $238, respectively, relating to variable interest entities)	14,386	14,255
Other Liabilities	28,818	23,561
Total liabilities	453,410	432,417
Direct
Assets
Premiums and Other Receivables, Net	7,109	6,044
Deferred Policy Acquisition Costs and Value of Business Acquired	25,099	24,490
Total assets	32,208	30,534
Liabilities
Future policy benefits (includes $0 and $716, respectively, relating to variable interest entities)	198,436	189,817
Policyholder account balances	209,028	201,748
Other policy-related balances (includes $0 and $238, respectively, relating to variable interest entities)	14,055	13,939
Other Liabilities	23,513	19,800
Total liabilities	445,032	425,304
Assumed
Assets
Premiums and Other Receivables, Net	543	555
Deferred Policy Acquisition Costs and Value of Business Acquired	16	120
Total assets	559	675
Liabilities
Future policy benefits (includes $0 and $716, respectively, relating to variable interest entities)	1,535	2,062
Policyholder account balances	1,209	975
Other policy-related balances (includes $0 and $238, respectively, relating to variable interest entities)	324	310
Other Liabilities	407	472
Total liabilities	3,475	3,819
Ceded
Assets
Premiums and Other Receivables, Net	18,429	16,103
Deferred Policy Acquisition Costs and Value of Business Acquired	(317)	(480)
Total assets	18,112	15,623
Liabilities
Future policy benefits (includes $0 and $716, respectively, relating to variable interest entities)	0	0
Policyholder account balances	(2)	(1)
Other policy-related balances (includes $0 and $238, respectively, relating to variable interest entities)	7	6
Other Liabilities	4,898	3,289
Total liabilities	$ 4,903	$ 3,294