Risk Management Activities and Derivative Transactions Offsetting for Derivative Liabilities (Details) $ in Millions	Dec. 31, 2022 USD ($)	Sep. 30, 2022 USD ($)	Mar. 31, 2022 Bond_issues
Offsetting Liabilities [Line Items]
Number of currency swaps outstanding \| Bond_issues			2
Accounts Receivable, before Allowance for Credit Loss, Current	$ 1,633	$ 1,899
Total derivatives not subject to master netting or similar arrangement	80	152
Gross amounts of recognized liabilities	1,178	1,160
Derivative Liability, Not Subject to Master Netting Arrangement	9	7
Forward Contract Derivative Asset, at Fair Value	9	4
Interest Rate Contract
Offsetting Liabilities [Line Items]
Gross amounts of recognized liabilities	857	905
Letter of Credit
Offsetting Liabilities [Line Items]
Amount of letters of credit outstanding	586	704
Fair Value, Inputs, Level 2
Offsetting Liabilities [Line Items]
Forward Contract Derivative Asset, at Fair Value	$ 9	$ 4

Fair value as of the balance sheet date of forward contract derivative assets.

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Amount, before allowance for credit loss, of right to consideration from customer for product sold and service rendered in normal course of business, classified as current.

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Fair value of financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset, not subject to a master netting arrangement.

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Fair value, before effects of master netting arrangements, of a financial liability or contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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The total amount of the contingent obligation under letters of credit outstanding as of the reporting date.

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Number of foreign currency exchange rate derivatives held by the entity at the reporting date.

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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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