Leases (Supplemental Balance Sheet Information) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Dec. 31, 2024
Property leases
Operating lease ROU assets	$ 3,167	$ 3,057
Short-term operating lease liabilities	627	628
Long-term operating lease liabilities	2,593	2,484
Operating lease liabilities	$ 3,220	$ 3,112
Weighted average remaining lease term	8 years	8 years
Weighted average discount rate	5.30%	4.98%
Operating lease, liability, current, statement of financial position [extensible enumeration]	Accounts Payable and Accrued Liabilities, Current	Accounts Payable and Accrued Liabilities, Current