Schedule III Supplementary Insurance Information (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	$ 11,115	$ 9,827
Liability for Unpaid Claims and Claims Adjustment Expense, Future Policy Benefits	118,527	120,009
Reserve for Unearned Premiums	21,318	21,324
Policy and Contract Claims	862	829
Premiums and Policy Fees	39,410	39,869	$ 39,839
Net Investment Income	14,053	16,079	15,810
Losses and Loss Expenses Incurred, Benefits	35,076	32,049	33,395
Amortization of Deferred Policy Acquisition Costs	5,236	5,330	5,157
Other Operating Expenses	10,788	10,887	10,883
Net Premiums Written	33,066	34,456	34,628
Corporate and Other
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	17	18
Liability for Unpaid Claims and Claims Adjustment Expense, Future Policy Benefits	6,421	166
Reserve for Unearned Premiums	357	(1)
Policy and Contract Claims	11	11
Premiums and Policy Fees	48	72	76
Net Investment Income	257	604	(195)
Losses and Loss Expenses Incurred, Benefits	860	915	1,546
Amortization of Deferred Policy Acquisition Costs	7	59	(97)
Other Operating Expenses	0	6	8
Net Premiums Written	0	0	0
Non-life insurance companies
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	2,631	2,551
Liability for Unpaid Claims and Claims Adjustment Expense, Future Policy Benefits	69,213	77,839
Reserve for Unearned Premiums	20,961	21,325
Policy and Contract Claims	0	0
Life insurance companies
Supplementary Insurance Information, by Segment [Line Items]
Deferred Policy Acquisition Costs	8,467	7,258
Liability for Unpaid Claims and Claims Adjustment Expense, Future Policy Benefits	42,893	42,004
Reserve for Unearned Premiums	0	0
Policy and Contract Claims	851	818
Commercial Insurance
Supplementary Insurance Information, by Segment [Line Items]
Premiums and Policy Fees	22,720	22,408	22,209
Net Investment Income	5,474	6,393	6,653
Losses and Loss Expenses Incurred, Benefits	20,425	16,985	17,415
Amortization of Deferred Policy Acquisition Costs	2,342	2,512	2,418
Other Operating Expenses	3,775	3,794	4,049
Net Premiums Written	21,486	22,044	21,928
Consumer Insurance
Supplementary Insurance Information, by Segment [Line Items]
Premiums and Policy Fees	16,642	17,389	17,554
Net Investment Income	8,322	9,082	9,352
Losses and Loss Expenses Incurred, Benefits	13,791	14,149	14,434
Amortization of Deferred Policy Acquisition Costs	2,887	2,759	2,836
Other Operating Expenses	7,013	7,087	6,826
Net Premiums Written	$ 11,580	$ 12,412	$ 12,700