Future Policy Benefits (Assumption Explanations) (Details) - Other Segments - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023
Life Insurance Product Line [Member] | Americas [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 12,100	$ 11,000
Future Policy Benefits Actual To Expected Variance	31	(24)
Impact Of Updating Discount Rate Recognized In OCI	$ 428	$ 490
Future Policy Benefits Actual To Expected Variance Increase Decrease	0.3% decrease	0.2% increase
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	3.5% decrease	4.4% increase
Life Insurance Product Line [Member] | CANADA
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 3,500	$ 3,400
Future Policy Benefits Actual To Expected Variance	3	(1)
Impact Of Updating Discount Rate Recognized In OCI	$ 239	$ 143
Future Policy Benefits Actual To Expected Variance Increase Decrease	0.1% decrease	None
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	6.7% decrease	4.3% increase
Life Insurance Product Line [Member] | EMEA [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 1,400	$ 1,200
Future Policy Benefits Actual To Expected Variance	(2)	(2)
Impact Of Updating Discount Rate Recognized In OCI	$ (33)	$ (2)
Future Policy Benefits Actual To Expected Variance Increase Decrease	0.1% decrease	0.2% decrease
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	2.3% decrease	0.2% decrease
Life Insurance Product Line [Member] | Asia Pacific [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 4,700	$ 4,300
Future Policy Benefits Actual To Expected Variance	(1)	7
Impact Of Updating Discount Rate Recognized In OCI	$ 57	$ 46
Future Policy Benefits Actual To Expected Variance Increase Decrease	None	0.2% decrease
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	1.2% decrease	1.1% increase
Insurance, Other | Americas [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 7,400	$ 4,200
Future Policy Benefits Actual To Expected Variance	(2)	4
Impact Of Updating Discount Rate Recognized In OCI	$ 84	$ (96)
Future Policy Benefits Actual To Expected Variance Increase Decrease	None	0.1% decrease
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	1.6% decrease	2.3% increase
Insurance, Other | CANADA
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 25,000	$ 50,000
Future Policy Benefits Actual To Expected Variance	0	4
Impact Of Updating Discount Rate Recognized In OCI	$ 2	$ (3)
Future Policy Benefits Actual To Expected Variance Increase Decrease	None	7.5% decrease
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	7.7% decrease	5.7% increase
Insurance, Other | EMEA [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 6,300	$ 5,600
Future Policy Benefits Actual To Expected Variance	2	(11)
Impact Of Updating Discount Rate Recognized In OCI	$ (154)	$ 46
Future Policy Benefits Actual To Expected Variance Increase Decrease	None	0.2% decrease
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	2.5% decrease	0.8% increase
Insurance, Other | Asia Pacific [Member]
Liability for Future Policy Benefit, by Product Segment [Line Items]
Net Liability For Future Policy Benefits At Original Discount Rate	$ 10,500	$ 6,100
Future Policy Benefits Actual To Expected Variance	0	(1)
Impact Of Updating Discount Rate Recognized In OCI	$ (97)	$ (136)
Future Policy Benefits Actual To Expected Variance Increase Decrease	None	None
Impact Of Updating Discount Rate Recognized In OCI Increase Decrease	1.6% increase	2.7% increase