Policy Claims and Benefits (Claims Development) (Details) - Life Insurance Product Line [Member] - USD ($) $ in Millions		Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012
Claims Development [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net		$ 1,616
Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	1,450
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented	[1]	98
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	2,149
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net		797
Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	2,863
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net, Not Separately Presented	[1]	152
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	3,530
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net		819
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	283	$ 274	$ 259	$ 243	$ 222	$ 185	$ 135	$ 49
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	313	308	303	293	285	282	278	207
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		7
Short-duration Insurance Contracts, Accident Year 2012 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	272	268	264	258	252	244	222	109
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	297	297	298	299	298	297	309	$ 323
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		0
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	294	282	260	235	209	144	50
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	329	327	313	300	303	312	292
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		11
Short-duration Insurance Contracts, Accident Year 2013 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	302	297	292	286	277	249	114
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	337	336	336	337	339	333	$ 349
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		0
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	241	228	205	177	135	34
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	285	283	270	264	299	276
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		13
Short-duration Insurance Contracts, Accident Year 2014 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	364	356	349	337	305	129
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	399	396	397	396	411	$ 408
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		0
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	221	201	167	118	49
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	266	266	249	256	277
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		21
Short-duration Insurance Contracts, Accident Year 2015 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	431	422	407	361	146
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	462	462	465	461	$ 460
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		0
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	152	133	97	38
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	219	212	205	227
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		24
Short-duration Insurance Contracts, Accident Year 2016 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	451	437	393	185
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	497	501	500	$ 501
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		1
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	115	87	35
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	214	214	211
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		34
Short-duration Insurance Contracts, Accident Year 2017 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	448	403	190
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	509	514	$ 485
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		6
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	106	32
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	270	253
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		76
Short-duration Insurance Contracts, Accident Year 2018 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	415	183
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	538	$ 538
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		28
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Asia Pacific [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	38
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	253
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		141
Short-Duration Insurance Contract, Accident Year 2019 [Member] | Americas [Member]
Claims Development [Line Items]
Short-duration Insurance Contracts, Cumulative Paid Claims and Allocated Claim Adjustment Expense, Net	[1]	180
Short-duration Insurance Contracts, Incurred Claims and Allocated Claim Adjustment Expense, Net	[1]	491
Short-duration Insurance Contracts, Incurred but Not Reported (IBNR) Claims Liability, Net		$ 213

[1] 2012-2018 Unaudited.