Investment in ATC (Tables)

6 Months Ended

Jun. 30, 2017

Equity Method Investments and Joint Ventures [Abstract]

ALLETE's Investment in ATC [Table Text Block]

ALLETE’s Investment in ATC
Millions
Equity Investment Balance as of December 31, 2016		$135.6
Cash Investments	5.0
Equity in ATC Earnings	11.4
Distributed ATC Earnings	(8.9		)
Equity Investment Balance as of June 30, 2017		$143.1