Consolidated Statements of Comprehensive Income/(Loss) - USD ($) $ in Millions	12 Months Ended
	Dec. 31, 2025	Dec. 31, 2024	Dec. 31, 2023
NET INCOME	$ 21.0	$ 13.8	$ 35.7
Unfunded pension and other postretirement activity:
Prior service cost for the period, net of income tax benefit/(expense)	0.2	0.1	(0.3)
Net loss for the period, net of income tax benefit/(expense)	1.5	(0.1)	(1.3)
Reclassification to earnings, net of income tax benefit/(expense)	1.0	0.1	0.2
Total change in unfunded pension obligation	2.7	(0.1)	1.4
Other comprehensive income / (loss)	1.8	(0.7)	(2.2)
Net comprehensive income / (loss)	34.8	13.1	33.5
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Noncontrolling Interest	13.0	0.0	0.0
Other Comprehensive Income (Loss), Net of Tax, Portion Attributable to Parent	21.8	13.1	33.5
Income tax (expense)/benefit on prior service cost related to pension and postretirement activity	0.0	(0.1)	0.1
Income tax (expense)/benefit on net loss related to pension and postretirement activity	(0.6)	0.1	0.3
Tax expense (benefit)	(22.9)	3.0	(6.6)
Other comprehensive income before reclassifications	0.7	0.0
Net income (loss)	33.0	13.8	35.7
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, after Tax	(0.9)	(0.8)	(0.8)
Accumulated Defined Benefit Plans Adjustment Attributable to Parent [Member]
Unfunded pension and other postretirement activity:
Other comprehensive income / (loss)	14.0	0.1
Other comprehensive income before reclassifications	0.7	0.0
Reclassification out of Accumulated Other Comprehensive Income [Member]
Unfunded pension and other postretirement activity:
Tax expense (benefit)	(0.4)	(0.1)	(0.0)
Other Comprehensive Income (Loss), Cash Flow Hedge, Gain (Loss), Reclassification, Tax	$ (0.1)	$ (0.2)	$ (0.2)