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Commitments and Contingencies - Schedule of Estimated Accrued Costs (Details)
$ in Millions
 3 Months Ended
Mar. 31, 2023
USD ($)
Minnesota and Indiana Gas Service Territories  
Loss Contingencies [Line Items]  
Liability recorded for environmental loss contingencies $ 16
Minnesota and Indiana Gas Service Territories | Minimum  
Loss Contingencies [Line Items]  
Estimated remediation costs $ 12
Years to resolve contingency 5 years
Minnesota and Indiana Gas Service Territories | Maximum  
Loss Contingencies [Line Items]  
Estimated remediation costs $ 51
Years to resolve contingency 50 years
Minnesota Service Territory | CERC  
Loss Contingencies [Line Items]  
Liability recorded for environmental loss contingencies $ 14
Minnesota Service Territory | CERC | Minimum  
Loss Contingencies [Line Items]  
Estimated remediation costs $ 11
Years to resolve contingency 5 years
Minnesota Service Territory | CERC | Maximum  
Loss Contingencies [Line Items]  
Estimated remediation costs $ 44
Years to resolve contingency 50 years