Supplementary Insurance Information (Details) - USD ($) $ in Millions		12 Months Ended
		Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		$ 3,616	$ 3,512
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		54,729	51,383
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		6,413	5,711
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		11,694	11,297	$ 10,544
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		2,575	2,520	2,139
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		11,779	10,894	9,744
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		383	330	423
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	1,881	1,944	1,862
US Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		1,816	1,806
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		12,245	11,969
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		2,578	2,143
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		5,838	5,729	5,534
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		714	769	730
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		5,979	5,339	5,131
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		200	199	180
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	679	697	698
US Non-Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		255	313
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		23,104	23,728
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		18	18
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		53	39	27
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		999	931	706
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		764	737	442
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		52	31	109
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	109	113	106
Canada Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		195	200
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		3,474	3,260
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		292	219
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		1,052	1,066	1,024
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		207	205	199
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		909	857	848
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		16	12	13
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	201	249	251
Canada Non-Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		16	23
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		4	42
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		83	89	43
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		1	3	2
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		68	80	37
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		0	0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	3	4	2
EMEA Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		264	250
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		1,379	1,197
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		1,389	1,109
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		1,555	1,442	1,424
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		72	73	66
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		1,389	1,205	1,233
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		31	36	27
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	186	199	179
EMEA Non-Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		5,881	5,703
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		66	51
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		252	218	195
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		193	195	134
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		163	175	116
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		0	0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	50	52	37
Asia Pacific Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		1,045	927
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		3,568	2,837
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		2,059	2,121
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		2,681	2,568	2,296
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		107	104	96
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		2,293	2,317	1,885
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		65	36	92
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	274	223	262
Asia Pacific Non-Traditional Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		41	16
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		4,187	2,215
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		2	2
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		180	146	1
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		85	46	40
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		206	162	40
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		19	16	2
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	25	27	19
Corporate And Other Segment Reporting Information [Member]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information [Line Items]
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Deferred Policy Acquisition Cost		0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Liability for Future Policy Benefit, Loss, Claim and Loss Expense		875	451
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Policy Claim and Benefit Payable		5	6
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Premium Revenue		0	0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Net Investment Income		197	194	166
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Benefit, Claim, Loss and Settlement Expenses		8	22	12
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Amortization of Deferred Policy Acquisition Cost		0	0	0
SEC Schedule, 12-16, Insurance Companies, Supplementary Insurance Information, Other Operating Expense	[1]	$ 354	$ 380	$ 308

[1] Includes policy acquisition costs and other insurance expenses, excluding amortization of DAC. Also includes other operating expenses, interest expense, and collateral finance and securitization expense.