XML 100 R76.htm IDEA: XBRL DOCUMENT 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