Regulatory Matters (Tables)

3 Months Ended

Mar. 31, 2022

Regulated Operations [Abstract]

Regulatory Assets and Liabilities [Table Text Block]

Regulatory Assets and Liabilities	March 31, 2022	December 31, 2021
Millions
Current Regulatory Assets (a)
Fuel Adjustment Clause	$39.8	—
Total Current Regulatory Assets	39.8	—
Non-Current Regulatory Assets
Defined Benefit Pension and Other Postretirement Benefit Plans	223.2	$226.4
Income Taxes	101.5	104.7
Cost Recovery Riders	60.6	63.2
Asset Retirement Obligations	33.5	33.1
Fuel Adjustment Clause	18.5	56.4
Manufactured Gas Plant	17.4	17.0
PPACA Income Tax Deferral	4.3	4.3
Residential Customer Interim Rate Adjustment	2.0	—
Other	3.2	6.7
Total Non-Current Regulatory Assets	464.2	511.8
Total Regulatory Assets	$504.0	$511.8
Current Regulatory Liabilities (b)
Fuel Adjustment Clause	$4.1	$5.0
Transmission Formula Rates Refund	2.9	3.1
Other	0.7	0.5
Total Current Regulatory Liabilities	7.7	8.6
Non-Current Regulatory Liabilities
Income Taxes	344.8	353.4
Wholesale and Retail Contra AFUDC	83.0	83.7
Plant Removal Obligations	54.2	52.6
North Dakota Investment Tax Credits	13.7	12.2
Defined Benefit Pension and Other Postretirement Benefit Plans	26.5	28.1
Boswell Units 1 and 2 Net Plant and Equipment	1.6	0.4
Other	9.6	5.7
Total Non-Current Regulatory Liabilities	533.4	536.1
Total Regulatory Liabilities	$541.1	$544.7

(a)Current regulatory assets are presented within Prepayments and Other on the Consolidated Balance Sheet.

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