Segment Information (Total Assets of Reportable Segments) (Details) - USD ($) $ in Millions	Mar. 31, 2020	Dec. 31, 2019
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 75,654	$ 76,731
Americas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	40,686	44,470
CANADA
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	4,410	4,425
EMEA [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	9,975	10,534
Asia Pacific [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	10,589	9,357
Corporate and Other [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	9,994	7,945
Life Insurance Product Line [Member] | Americas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	19,418	19,353
Life Insurance Product Line [Member] | CANADA
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	4,366	4,361
Life Insurance Product Line [Member] | EMEA [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	3,924	4,032
Life Insurance Product Line [Member] | Asia Pacific [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	7,118	6,800
Nontraditional Long-Duration Contracts [Member] | Americas [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	21,268	25,117
Nontraditional Long-Duration Contracts [Member] | CANADA
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	44	64
Nontraditional Long-Duration Contracts [Member] | EMEA [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	6,051	6,502
Nontraditional Long-Duration Contracts [Member] | Asia Pacific [Member]
Segment Reporting, Asset Reconciling Item [Line Items]
Assets	$ 3,471	$ 2,557