Regulatory Matters (Tables)

6 Months Ended

Jun. 30, 2019

Regulated Operations [Abstract]

Regulatory Assets and Liabilities [Table Text Block]

Regulatory Assets and Liabilities	June 30, 2019		December 31, 2018
Millions
Non-Current Regulatory Assets
Defined Benefit Pension and Other Postretirement Benefit Plans		$216.5		$218.5
Income Taxes	102.2		105.5
Asset Retirement Obligations	32.3		32.6
Boswell 1 and 2 Net Plant and Equipment	13.5		16.3
Cost Recovery Riders	10.0		—
Manufactured Gas Plant	8.1		8.0
PPACA Income Tax Deferral	4.9		5.0
Other	3.7		3.6
Total Non-Current Regulatory Assets		$391.2		$389.5
Current Regulatory Liabilities (a)
Provision for Interim Rate Refund (b)	—			$40.0
Transmission Formula Rates Refund		$3.1	4.4
Provision for Tax Reform Refund (c)	0.4		10.7
Total Current Regulatory Liabilities	3.5		55.1
Non-Current Regulatory Liabilities
Income Taxes	386.2		396.4
Wholesale and Retail Contra AFUDC	70.6		64.4
Plant Removal Obligations	29.3		25.1
North Dakota Investment Tax Credits	12.3		14.7
Conservation Improvement Program	7.0		1.5
Transmission Formula Rates Refund	0.8		1.6
Cost Recovery Riders	—		6.9
Other	2.6		1.5
Total Non-Current Regulatory Liabilities	508.8		512.1
Total Regulatory Liabilities		$512.3		$567.2

(a) Current regulatory liabilities are presented within Other Current Liabilities on the Consolidated Balance Sheet.

(b) This amount was refunded to Minnesota Power’s regulated retail customers in the second quarter of 2019.

(c)

Provision for Tax Reform Refund related to the income tax benefits of the TCJA in 2018 was refunded to Minnesota Power customers in the first quarter of 2019 and will be refunded to SWL&P customers in 2019 and 2020.