v3.26.1
Segment Reporting - Revenues and Operating (Loss) Earnings by Reportable Segment (Details)
$ in Millions
 3 Months Ended 6 Months Ended
Jun. 30, 2026
USD ($)
Jun. 30, 2025
USD ($)
Jun. 30, 2026
USD ($)
segment
Jun. 30, 2025
USD ($)
Segment Reporting, Descriptive Information [Abstract]        
Number of reportable segments | segment     3  
Revenues $ 167.3 $ 159.0 $ 312.0 $ 313.0
Cost of sales 130.9 125.6 250.0 249.4
Depreciation and amortization 20.8 23.7 42.7 48.4
Selling, general and administrative 19.0 18.0 34.4 39.6
Segment operating income 2.1 (8.7) (10.0) (25.2)
Unallocated corporate expenses (3.4) (9.0) (11.3) (20.2)
Interest income 0.0 0.0 0.0 0.3
Interest expense (12.5) (11.0) (24.2) (21.3)
(Gain) loss on debt extinguishment 0.3 0.0 0.3 (1.2)
Net loss before income tax (10.1) (19.7) (33.9) (47.4)
Location, Statement of Income, Balance [Axis]: us-gaap:CostOfGoodsAndServicesSold        
Segment Reporting, Descriptive Information [Abstract]        
Unallocated corporate expenses (1.0) (0.6) (1.9) (1.4)
Location, Statement of Income, Balance [Axis]: us-gaap:DepreciationDepletionAndAmortization        
Segment Reporting, Descriptive Information [Abstract]        
Unallocated corporate expenses (0.7) (0.4) (0.9) (1.0)
Location, Statement of Income, Balance [Axis]: us-gaap:OtherAssetImpairmentCharges        
Segment Reporting, Descriptive Information [Abstract]        
Unallocated corporate expenses 5.7 (0.4) 5.3 (0.8)
Location, Statement of Income, Balance [Axis]: us-gaap:SellingGeneralAndAdministrativeExpense        
Segment Reporting, Descriptive Information [Abstract]        
Unallocated corporate expenses (7.4) (7.6) (13.8) (17.0)
Eliminations        
Segment Reporting, Descriptive Information [Abstract]        
Revenues 0.2 0.4 0.4 0.7
Cost of sales (0.2) (0.4) (0.4) (0.7)
Total        
Segment Reporting, Descriptive Information [Abstract]        
Segment operating income 5.5 0.3 1.3 (5.0)
Rocky Mountains | Operating Segments        
Segment Reporting, Descriptive Information [Abstract]        
Revenues 50.8 54.2 89.4 102.1
Cost of sales 40.9 40.2 74.7 77.9
Depreciation and amortization 5.4 6.5 11.3 13.3
Selling, general and administrative 2.0 1.9 3.9 3.8
Other segment items 2.3 2.3 3.1 4.0
Segment operating income 0.2 3.3 (3.6) 3.1
Southwest | Operating Segments        
Segment Reporting, Descriptive Information [Abstract]        
Revenues 64.7 59.0 118.4 124.4
Cost of sales 52.4 48.7 98.2 98.4
Depreciation and amortization 7.5 8.4 15.4 16.7
Selling, general and administrative 2.9 3.0 6.0 6.4
Other segment items 1.7 0.6 2.0 1.6
Segment operating income 0.2 (1.7) (3.2) 1.3
Northeast /Mid-Con | Operating Segments        
Segment Reporting, Descriptive Information [Abstract]        
Revenues 52.0 46.2 104.6 87.2
Cost of sales 36.7 36.6 75.5 72.4
Depreciation and amortization 7.2 8.4 15.1 17.4
Selling, general and administrative 1.6 1.5 3.2 3.1
Other segment items 1.4 1.0 2.7 3.7
Segment operating income $ 5.1 $ (1.3) $ 8.1 $ (9.4)