Long-term and Short-term Debt Long-term and Short-term Debt (Narrative - Line of Credit) (Details) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2024	Dec. 31, 2023	Dec. 31, 2022	Dec. 01, 2037
Committed Credit Facility Six [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	$ 405
Line of Credit Facility, Maximum Borrowing Capacity	2,896
Line of Credit Facility, Current Borrowing Capacity	2,900
General Credit Facility Three [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	2,703
Line of Credit Facility, Maximum Borrowing Capacity	3,000
Committed Credit Facility Three [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	0
Line of Credit Facility, Maximum Borrowing Capacity	350
Committed Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Remaining Borrowing Capacity	405
Line of Credit Facility, Maximum Borrowing Capacity	3,246
Committed Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity	3,200
Line of Credit Facility, Commitment Fee Amount	9	$ 9	$ 9
General Credit Facility [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Commitment Fee Amount	$ 7	$ 6	$ 8
Forecast [Member] | Committed Credit Facility Six [Member]
Line of Credit Facility [Line Items]
Line of Credit Facility, Maximum Borrowing Capacity				$ 2,000