Regulatory Environment - Acquisition of a Wind Energy Generation Facility in Wisconsin (Details) - Forward Wind Energy Center Acquisition - WPS	1 Months Ended
Oct. 31, 2017 wind_turbines utility MW
Public Utilities, General Disclosures [Line Items]
Number Of Additional Utilities Purchased Forward Wind Energy Center \| utility	2
Wind Turbines Forward Energy Center \| wind_turbines	86
Capacity Forward Wind Energy Center \| MW	138

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