Consolidated Balance Sheets - USD ($) $ in Millions	Dec. 31, 2025	Dec. 31, 2024
Current assets:
Cash and cash equivalents	$ 82.9	$ 54.0
Restricted cash	0.1	0.1
Accounts receivable, net	161.1	106.8
Inventories	70.3	70.5
Taxes applicable to subsequent years	150.4	137.1
Regulatory Assets, Current	61.1	82.0
Income Taxes Receivable, Current	24.2	27.1
Prepayments and other current assets	9.1	7.5
Total current assets	559.1	485.0
Carrying Value	2,885.8	2,571.4
Assets, Noncurrent [Abstract]
Regulatory Assets, Noncurrent	137.4	140.0
Intangible assets, net of amortization	166.9	175.1
Other Assets, Noncurrent	31.8	45.9
Assets, Noncurrent	3,221.9	2,932.4
Total assets	3,781.0	3,417.4
LIABILITIES AND SHAREHOLDER'S EQUITY
Current portion - long-term debt	0.2	704.4
Accounts payable	144.0	132.1
Accrued interest	19.6	22.8
Accrued taxes	145.7	115.4
Customer security deposits	8.8	14.2
Regulatory Liability, Current	1.8	10.3
Other current liabilities	57.4	35.0
Total current liabilities	377.5	1,034.2
Non-current liabilities:
Long-term debt	1,798.1	1,425.6
Deferred Income Tax Liabilities, Net	233.0	249.6
Taxes payable	150.9	137.5
Regulatory Liability, Noncurrent	189.5	169.4
Pension, retiree and other benefits	16.5	30.7
Other deferred credits	7.9	8.3
Total non-current liabilities	2,395.9	2,021.1
Liabilities	2,773.4	3,055.3
Commitments and contingencies
Redeemable Noncontrolling Interest, Equity, Carrying Amount	594.7
Members' Equity	3,049.3
Common shareholder's equity:
Other paid-in capital		3,040.5
Accumulated other comprehensive income/(loss)	15.7	(5.3)
Retained earnings / (deficit)	(2,652.1)	(2,673.1)
Equity, Attributable to Parent	412.9
Total common shareholder's equity		362.1
Total Liabilities and Shareholder's Equity	3,781.0	3,417.4
Accumulated Depreciation, Depletion and Amortization, Property, Plant, and Equipment	$ 647.3	$ 571.7