XML 81 R70.htm IDEA: XBRL DOCUMENT v3.21.2
Other Commitments And Contingencies (Narrative) (Details)
$ in Millions
 31 Months Ended
Mar. 31, 2021
USD ($)
Oct. 01, 2021
USD ($)
Sep. 30, 2021
USD ($)
Rate
Dec. 31, 2020
USD ($)
Jul. 26, 2019
USD ($)
Other Commitments And Contingencies [Line Items]          
Guaranty Liabilities     $ 574.4    
Litigation Settlement, Amount Awarded to Other Party         $ 143.0
Recorded reserves to cover environmental remediation at various sites     $ 92.3 $ 92.6  
Wind Power Purchase Agreement, Purchase Percentage | Rate     100.00%    
Restructuring and Related Cost, Expected Cost     $ 42.0    
Subsequent Event          
Other Commitments And Contingencies [Line Items]          
Guaranty Liabilities   $ 774.4      
MGP Sites          
Other Commitments And Contingencies [Line Items]          
Number of waste disposal sites identified by program     54    
Liability for Estimated Remediation Costs     $ 86.3 85.0  
Reasonably possible remediation costs variance from reserve     17.0    
Columbia Of Massachusetts          
Other Commitments And Contingencies [Line Items]          
Pipeline Replacement Expenses $ 258.0        
Standby Letters of Credit          
Other Commitments And Contingencies [Line Items]          
Long-term Line of Credit     $ 14.1 $ 15.2