XML 75 R52.htm IDEA: XBRL DOCUMENT v3.20.2
Revenue Recognition Revenue Recognition (Allowance for Credit Losses) (Details) - USD ($)
$ in Millions
 3 Months Ended 9 Months Ended
Sep. 30, 2020
Sep. 30, 2020
Jun. 30, 2020
Dec. 31, 2019
Financing Receivable, Allowance for Credit Loss [Line Items]        
Allowance for Credit Loss $ 39.3 $ 39.3 $ 31.4 $ 13.0
Current period provisions 10.5 37.3    
Write-offs charged against allowance (4.8) (21.1)    
Recoveries of amounts previously written off 2.2 10.1    
Gas Distribution Operations        
Financing Receivable, Allowance for Credit Loss [Line Items]        
Allowance for Credit Loss 31.5 31.5 25.4 9.1
Current period provisions 8.2 30.6    
Write-offs charged against allowance (4.3) (18.1)    
Recoveries of amounts previously written off 2.2 9.9    
Electric Operations        
Financing Receivable, Allowance for Credit Loss [Line Items]        
Allowance for Credit Loss 7.0 7.0 5.2 3.1
Current period provisions 2.3 6.7    
Write-offs charged against allowance (0.5) (3.0)    
Recoveries of amounts previously written off 0.0 0.2    
Corporate and Other        
Financing Receivable, Allowance for Credit Loss [Line Items]        
Allowance for Credit Loss 0.8 0.8 $ 0.8 $ 0.8
Current period provisions 0.0 0.0    
Write-offs charged against allowance 0.0 0.0    
Recoveries of amounts previously written off $ 0.0 $ 0.0