Reportable Segments - Depreciation and amortization expense by segment (Details) - USD ($) $ in Millions	3 Months Ended	6 Months Ended
Jun. 30, 2026	Jun. 30, 2025	Jun. 30, 2026	Jun. 30, 2025
Reportable Segments
Depreciation and amortization	$ 30.7	$ 22.5	$ 54.4	$ 43.9
Operating Segment \| Utilities
Reportable Segments
Depreciation and amortization	14.2	14.6	28.3	28.8
Operating Segment \| Energy
Reportable Segments
Depreciation and amortization	14.4	6.4	22.3	12.3
Corporate and non-allocated costs
Reportable Segments
Depreciation and amortization	$ 2.1	$ 1.5	$ 3.8	$ 2.8

The aggregate expense recognized in the current period that allocates the cost of tangible assets, intangible assets, or depleting assets to periods that benefit from use of the assets.

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+ Details

- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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+ Details