ACQUISITION - PURCHASE PRICE ALLOCATION (Details) - Forward Wind Energy Center Acquisition - USD ($) $ in Millions	1 Months Ended
Apr. 30, 2018	Apr. 02, 2018
Business Acquisition [Line Items]
Purchase price	$ 172.9
WPS
Business Acquisition [Line Items]
Current assets		$ 0.2
Net property, plant, and equipment		$ 76.9
Purchase price	$ 77.1

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Amount of consideration transferred, consisting of acquisition-date fair value of assets transferred by the acquirer, liabilities incurred by the acquirer, and equity interest issued by the acquirer.

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Amount of assets that are expected to be realized or consumed within one year or the normal operating cycle, if longer, acquired at the acquisition date.

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The amount of property, plant, and equipment recognized as of the acquisition date.

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