Other Assets and Liabilites - Schedule of Right of Use Assets and Future Maturities of Lease Liabilities (Details) - USD ($) $ in Millions	3 Months Ended
	Mar. 31, 2024	Mar. 31, 2023	Dec. 31, 2023
Right of Use Assets
Right-of-Use Asset, Operating Leases	$ 1,033		$ 1,057
Right-of-Use Asset, Finance Leases	$ 9		$ 10
Operating Lease, Right-of-Use Asset, Statement of Financial Position [Extensible Enumeration]	Other assets (including $1,359 and $1,311 at fair value, respectively)		Other assets (including $1,359 and $1,311 at fair value, respectively)
Operating Lease Liabilities, Payments Due
Total lease liabilities	$ 1,355		$ 1,387
Operating Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities		Other Liabilities
Weighted Average Remaining Lease Term, Operating Leases	6 years 1 month 6 days		6 years 2 months 12 days
Weighted Average Discount Rate, Percent, Operating Leases	3.20%		3.10%
Operating Lease, Cost	$ 77	$ 73
Finance Lease Liabilities, Payments, Due
Total lease liabilities	$ 11		$ 12
Finance Lease, Liability, Statement of Financial Position [Extensible Enumeration]	Other Liabilities		Other Liabilities
Weighted Average Remaining Lease Term, Finance Leases	6 years 7 months 6 days		6 years 7 months 6 days
Weighted Average Discount Rate, Percent, Finance Leases	5.20%		5.10%