XML 97 R77.htm IDEA: XBRL DOCUMENT v3.10.0.1
Acquisitions - Forward Wind Energy Center (Details) - Forward Wind Energy Center Acquisition
$ in Millions
1 Months Ended
Apr. 30, 2018
USD ($)
wind_turbines
utility
MW
Business Acquisition [Line Items]  
Number of wind turbines at Forward Wind Energy Center | wind_turbines 86
Capacity of Foward Wind Energy Center | MW 138
Total purchase price $ 172.9
WPS  
Business Acquisition [Line Items]  
Number of utilities along with WPS that entered in an agreement to purchase Forward Wind Energy Center | utility 2
WPS's share of Forward Wind Energy Center's purchase price 44.60%
Percentage of Forward Wind Energy Center's output purchased by WPS 44.60%
Current assets $ 0.2
Net property, plant, and equipment 76.9
Total purchase price $ 77.1