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Other, Net (Details) - USD ($) $ in Millions	3 Months Ended		6 Months Ended
	Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Other, Net [Abstract]
Accounts receivable	$ 1.6	$ 1.5	$ 6.3	$ 3.5
Gas storage and other inventories	14.6	8.6	24.4	17.8
Customer deposits and credits	2.2	(1.6)	4.4	(5.4)
Income Tax Examination, Penalties Expense	0.0	(8.1)	0.0	(9.2)
Other, net	18.2	0.5	32.6	6.3
Miscellaneous Non-Operating Income (Expense)	$ (0.2)	$ 0.1	$ (2.5)	$ (0.4)

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The amount of estimated penalties recognized in the period arising from income tax examinations.

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Amount capitalized of allowance for funds used during construction.

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