Segment Information (Total Revenues of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2020	Mar. 31, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 3,204	$ 3,420
Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,672	1,795
CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	320	336
EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	485	493
Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	735	728
Corporate and Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	(8)	68
Life Insurance Product Line [Member] | Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,533	1,541
Life Insurance Product Line [Member] | CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	296	312
Life Insurance Product Line [Member] | EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	407	384
Life Insurance Product Line [Member] | Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	667	673
Nontraditional Long-Duration Contracts [Member] | Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	139	254
Nontraditional Long-Duration Contracts [Member] | CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	24	24
Nontraditional Long-Duration Contracts [Member] | EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	78	109
Nontraditional Long-Duration Contracts [Member] | Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 68	$ 55