REGULATORY MATTERS (Tables)

9 Months Ended

Sep. 30, 2024

Regulated Operations [Abstract]

Schedule of Regulatory Assets and Liabilities

The recovery, refund or credit to rates for these regulatory assets and liabilities will occur over the periods either specified by the applicable regulatory authority or over the corresponding period related to the asset or liability.

NOTE 2. REGULATORY MATTERS (Continued)

Regulatory Assets and Liabilities	September 30, 2024	December 31, 2023
Millions
Current Regulatory Assets (a)
Fuel Adjustment Clause	—	$8.7
Other	$0.6	0.6
Total Current Regulatory Assets	$0.6	$9.3
Non-Current Regulatory Assets
Defined Benefit Pension and Other Postretirement Plans	$214.5	$218.6
Income Taxes	81.7	88.1
Asset Retirement Obligations	39.9	37.7
Taconite Harbor	20.6	20.9
Manufactured Gas Plant	12.9	13.2
Cost Recovery Riders	8.6	33.8
PPACA Income Tax Deferral	3.8	3.9
Fuel Adjustment Clause	1.5	5.0
Other	2.6	4.2
Total Non-Current Regulatory Assets	$386.1	$425.4
Current Regulatory Liabilities (b)
Provision for Interim Rate Refund	$17.0	—
Fuel Adjustment Clause	10.0	—
Transmission Formula Rates Refund	—	$1.5
Other	0.8	2.4
Total Current Regulatory Liabilities	$27.8	$3.9
Non-Current Regulatory Liabilities
Income Taxes	$292.8	$310.0
Wholesale and Retail Contra AFUDC	76.2	78.0
Plant Removal Obligations	72.8	67.0
Non-Jurisdictional Land Sales	55.0	30.2
Defined Benefit Pension and Other Postretirement Benefit Plans	39.2	48.6
Investment Tax Credits	13.2	13.6
Boswell Units 1 and 2 Net Plant and Equipment	6.7	6.7
Fuel Adjustment Clause	0.6	15.5
Other	5.6	4.4
Total Non-Current Regulatory Liabilities	$562.1	$574.0

(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.