Insurance (Reconciliation of Disclosure to Liability) (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	$ 13,632
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	869
Total unpaid claims and allocated claims adjustment expense	14,501
Unallocated claims adjustment expenses	2
Discounting	(1,205)
Liability for unpaid claims and claim adjustment liabilities - short-duration	13,298
Liability for unpaid claims and claim adjustment liabilities - long-duration	6,715
Liability for Claims and Claims Adjustment Expense	20,013	$ 18,591	$ 19,216	$ 17,788
UNITED STATES
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	10,198
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	180
Latin America
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	544
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	23
Group Life - Term
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	3,022
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	14
Group Life - Term | Asia
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	867
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	375
Group Long-Term Disability
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	7,176
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	166
Discounting	(1,100)	$ (1,200)
Protection Life
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	444
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	10
Protection Health
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	100
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	13
Other insurance lines - all segments combined
Short-duration Insurance Contracts, Reconciliation of Claims Development to Liability [Line Items]
Short-duration Insurance Contracts, Liability for Unpaid Claims and Allocated Claim Adjustment Expense, Net	2,023
Reinsurance Recoverable for Unpaid Claims and Claims Adjustments	$ 291