Segment Information (Total Revenues of Reportable Segments) (Details) - USD ($) $ in Millions	3 Months Ended		9 Months Ended
	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2020	Sep. 30, 2019
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 3,643	$ 3,628	$ 10,453	$ 10,515
Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,998	1,993	5,635	5,674
CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	332	349	985	1,027
EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	500	495	1,492	1,472
Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	746	731	2,192	2,152
Corporate and Other [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	67	60	149	190
Life Insurance Product Line [Member] | Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	1,599	1,610	4,774	4,735
Life Insurance Product Line [Member] | CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	309	325	916	955
Life Insurance Product Line [Member] | EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	390	378	1,168	1,132
Life Insurance Product Line [Member] | Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	680	685	1,983	1,992
Nontraditional Long-Duration Contracts [Member] | Americas [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	399	383	861	939
Nontraditional Long-Duration Contracts [Member] | CANADA
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	23	24	69	72
Nontraditional Long-Duration Contracts [Member] | EMEA [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	110	117	324	340
Nontraditional Long-Duration Contracts [Member] | Asia Pacific [Member]
Segment Reporting, Revenue Reconciling Item [Line Items]
Revenues	$ 66	$ 46	$ 209	$ 160