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v3.23.2

Risk Management Activities and Derivative Transactions Counterparty Credit Risk (Details) $ in Millions | 3 Months Ended | 9 Months Ended |
--- | --- | --- | ---
Jun. 30, 2023 USD ($) | Jun. 30, 2023 USD ($) Customers | Sep. 30, 2022 USD ($)
Derivative |  |  |
Accounts Receivable, before Allowance for Credit Loss, Current | $ | $ 1,514 | $ 1,514 | $ 1,899
Total derivatives not subject to master netting or similar arrangement | $ | $ 22 | $ 22 | $ 152
Two Largest Customer Percentage of Total Operating Revenue | 1600.00% |  |
Moody's, A1 Rating [Member] |  |  |
Derivative |  |  |
Banking Counterparties Credit Rating |  | A2 |
Natural Gas Banking Counterparties Credit Rating |  | A1 |
Moody's, Caa1 Rating [Member] |  |  |
Derivative |  |  |
Natural Gas Banking Counterparties Credit Rating |  | B1 |
Credit of Customers |  |  |
Derivative |  |  |
Number of customers that represent the percent of sales | Customers |  | 2 |
Number of customers that represent the percent of sales | Customers |  | 2 |

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- Definition 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. + References Reference 1: http://www.xbrl.org/2003/role/disclosureRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02(3)(a)(1)) -Publisher FASB -URI https://asc.fasb.org//1943274/2147480566/210-10-S99-1 Reference 2: http://www.xbrl.org/2003/role/exampleRef -Topic 210 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 1 -Subparagraph (c) -Publisher FASB -URI https://asc.fasb.org//1943274/2147483467/210-10-45-1 Reference 3: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 2 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-2 Reference 4: http://www.xbrl.org/2003/role/disclosureRef -Topic 310 -SubTopic 10 -Name Accounting Standards Codification -Section 45 -Paragraph 9 -Publisher FASB -URI https://asc.fasb.org//1943274/2147481990/310-10-45-9 + Details
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