Jointly-Owned Facilities and Assets (Tables)

12 Months Ended

Dec. 31, 2019

Jointly-Owned Facilities and Assets [Abstract]

Jointly-Owned Facilities and Assets [Table Text Block]

Minnesota Power’s investments in jointly-owned facilities and assets 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, 2019
Boswell Unit 4		$662.7		$258.9		$5.7	80
CapX2020	101.0		13.5		—		9.3 - 14.7
Total		$763.7		$272.4		$5.7
As of December 31, 2018
Boswell Unit 4		$650.1		$229.9		$6.4	80
CapX2020	101.0		11.0		—		9.3 - 14.7
Total		$751.1		$240.9		$6.4