Long-term Corporate Debt and Borrowing Arrangements (Narrative) (Details) - USD ($) $ in Millions	Mar. 31, 2025	Feb. 28, 2025	Dec. 31, 2024
Debt Instrument [Line Items]
Line of credit balance	$ 20,309
Remaining available capacity	2,998
Line of Credit | SBLC Facility
Debt Instrument [Line Items]
Line of credit balance	462
Letters of credit issued	405
Remaining available capacity	57
Loans Payable | Floating Rate Term Loan
Debt Instrument [Line Items]
Long-term debt	$ 488	$ 500	$ 0