Goodwill and Other Intangible Assets - Schedule of Carrying Value and Accumulated Amortization of Intangible Assets (Detail) - USD ($) $ in Millions		Dec. 31, 2025	Dec. 31, 2024
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		$ 27.0	$ 27.0
Accumulated Amortization		13.8	12.0
Customer Lists [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		17.0	17.0
Accumulated Amortization		9.2	8.2
Noncompete Agreements [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		3.1	3.1
Accumulated Amortization		2.7	2.3
Patents [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount	[1]	6.6	6.6
Accumulated Amortization	[1]	1.6	1.2
Other Intangible Assets [Member]
Finite-Lived Intangible Assets [Line Items]
Gross Carrying Amount		0.3	0.3
Accumulated Amortization		$ 0.3	$ 0.3

[1] (1) Includes amounts related to patented technology developed by Marlin Gas Services and the acquisition of Planet Found