Indebtedness: (Schedule of Fair Value) (Details) $ in Millions	Sep. 30, 2023 USD ($)
Level 1
Debt Instrument [Line Items]
Fair value of outstanding long-term debt	$ 36,217
Level 2
Debt Instrument [Line Items]
Fair value of outstanding long-term debt	$ 6,356

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details