v3.26.1
Supplementary Financial Information - Schedule of Cash and Cash Equivalents (Details) - USD ($)
$ in Millions
 6 Months Ended
Jun. 30, 2026
Jun. 30, 2025
Cash, Cash Equivalents, Restricted Cash, And Restricted Cash Equivalents [Roll Forward]    
Cash and cash equivalents, beginning of the period $ 108.2 $ 41.8
Restricted cash included in other assets (non-current), beginning of period 0.6 0.5
Cash, cash equivalents and restricted cash, beginning of period 108.8 42.3
Cash and cash equivalents, end of the period 87.8 27.8
Restricted cash included in other assets (non-current), end of period 0.6 0.6
Cash, cash equivalents and restricted cash, end of period 88.4 28.4
Supplemental cash flow information:    
Cash paid for interest 3.9 23.8
Cash paid for income taxes, net of refunds 1.6 3.6
Non-cash investing and financing activities:    
Accrued interest and fees capitalized into principal debt 29.0 2.5
Property, plant and equipment included in accounts payable or accrued expenses 1.6 0.7
Spectrum Segment    
Non-cash investing and financing activities:    
Property, plant and equipment included in accounts payable or accrued expenses 0.3 0.2
Spectrum Segment | Bridge Loan | Bridge Loan Facility | Line of Credit    
Non-cash investing and financing activities:    
Interest costs capitalized 0.8  
Discontinued Operations    
Cash, Cash Equivalents, Restricted Cash, And Restricted Cash Equivalents [Roll Forward]    
Cash and cash equivalents classified in Assets held for sale, beginning of period 3.8 7.0
Restricted cash classified in Assets held for sale, beginning of period 0.1 0.0
Cash and cash equivalents and restricted cash classified in Assets held for sale, beginning of period 3.9 7.0
Cash and cash equivalents classified in Assets held for sale, end of period 2.0 5.6
Restricted cash classified in Assets held for sale, end of period 0.0 0.0
Cash and cash equivalents and restricted cash classified in Assets held for sale, end of period $ 2.0 $ 5.6