Other Assets - Equity Method Investments and Leases - Balance Sheet Amounts Related to Leases (Details) - USD ($) $ in Millions	Dec. 31, 2021	Dec. 31, 2020
Deferred Costs, Capitalized, Prepaid, and Other Assets Disclosure [Abstract]
Other assets—ROU assets	$ 4,268	$ 4,419
Other liabilities and accrued expenses—Lease liabilities	$ 5,157	$ 5,327
Weighted average:
Remaining lease term, in years	8 years 10 months 24 days	9 years 6 months
Discount rate (as a percent)	3.10%	3.20%
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible List]	Other assets	Other assets
Operating Lease, Liability, Statement of Financial Position [Extensible List]	Accounts Payable and Accrued Liabilities	Accounts Payable and Accrued Liabilities