Schedule III Supplementary Insurance Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	$ 12,694	$ 10,994
Liability for Unpaid Losses and Loss Adjustment Expenses, Future Policy Benefits	128,574	123,825
Unearned Premiums	19,248	19,030
Policy and Contract Claims	864	860
Premiums and Policy Fees	33,405	34,309	$ 37,125
Net Investment Income	12,476	14,179	14,065
Losses and Loss Expenses Incurred, Benefits	31,166	33,564	36,142
Amortization of Deferred Policy Acquisition Costs	5,386	4,288	4,521
Other Operating Expenses	7,634	7,396	8,667
Net Premiums Written	26,606	25,756	29,233
General Insurance
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	2,890	2,587
Liability for Unpaid Losses and Loss Adjustment Expenses, Future Policy Benefits	113,696	73,530
Unearned Premiums	19,235	18,795
Policy and Contract Claims	14	0
Premiums and Policy Fees	27,505	26,026	29,586
Net Investment Income	2,668	3,668	3,554
Losses and Loss Expenses Incurred, Benefits	20,824	21,642	25,103
Amortization of Deferred Policy Acquisition Costs	4,596	3,765	4,121
Other Operating Expenses	5,222	5,100	5,967
Net Premiums Written	26,407	25,438	28,393
Life and Retirement
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	9,804	8,407
Liability for Unpaid Losses and Loss Adjustment Expenses, Future Policy Benefits	13,431	44,615
Unearned Premiums	13	0
Policy and Contract Claims	843	851
Premiums and Policy Fees	5,261	6,844	4,878
Net Investment Income	7,922	7,816	7,622
Losses and Loss Expenses Incurred, Benefits	7,692	8,607	6,945
Amortization of Deferred Policy Acquisition Costs	680	743	613
Other Operating Expenses	2,412	2,296	2,700
Net Premiums Written	0	0	0
Other Operations
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	0	0
Liability for Unpaid Losses and Loss Adjustment Expenses, Future Policy Benefits	1,447	5,680
Unearned Premiums	0	235
Policy and Contract Claims	7	9
Premiums and Policy Fees	39	712	1,845
Net Investment Income	(439)	(81)	(24)
Losses and Loss Expenses Incurred, Benefits	357	1,076	743
Amortization of Deferred Policy Acquisition Costs	5	(296)	(321)
Other Operating Expenses	0	0	0
Net Premiums Written	199	314	819
Legacy Portfolio
Supplementary Insurance Information, by Segment [Line Items]
Premiums and Policy Fees	600	727	816
Net Investment Income	2,325	2,776	2,913
Losses and Loss Expenses Incurred, Benefits	2,293	2,239	3,351
Amortization of Deferred Policy Acquisition Costs	105	76	108
Other Operating Expenses	0	0	0
Net Premiums Written	$ 0	$ 4	$ 21