Jointly-Owned Facilities and Projects (Tables)

12 Months Ended

Dec. 31, 2016

Jointly-Owned Facilities and Projects [Abstract]

Jointly-Owned Facilities and Projects [Table Text Block]

Minnesota Power’s investments in jointly-owned facilities and projects and the related ownership percentages are as follows:

Regulated Utility Plant	Plant in Service		Accumulated Depreciation		Construction Work in Progress		% Ownership
Millions
As of December 31, 2016
Boswell Unit 4		$668.1		$211.2		$8.1	80
CapX2020 Projects	101.2		5.9		—		9.3 - 14.7
Total		$769.3		$217.1		$8.1
As of December 31, 2015
Boswell Unit 4		$668.2		$195.0		$6.9	80
CapX2020 Projects	101.1		3.4		—		9.3 - 14.7
Total		$769.3		$198.4		$6.9