Equity Investments (Tables)

6 Months Ended

Jun. 30, 2019

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, 2018		$128.1
Cash Investments	2.7
Equity in ATC Earnings	10.4
Distributed ATC Earnings	(8.2		)
Amortization of the Remeasurement of Deferred Income Taxes	0.6
Equity Investment Balance as of June 30, 2019		$133.6