v3.26.3
Fair Value (Tables)
 9 Months Ended
Sep. 30, 2026
Fair Value Disclosures [Abstract]  
Fair Value, by Balance Sheet Grouping
The carrying amounts and estimated fair values of the Company's financial assets and liabilities which were not recorded at fair value on the Condensed Consolidated Balance Sheets, were as follows (in millions):

As of September 30, 2026Estimated Fair Value
Financial AssetsCarrying AmountLevel 1Level 2Level 3Total
Cash and cash equivalents$109.0 $109.0 $— $— $109.0 
Financial Liabilities
Long-term debt
$3,237.4 
(1)
$— $3,076.6 $— $3,076.6 

(1)The carrying amount of long-term debt excluded $4.7 million of unamortized debt issuance costs.

As of December 31, 2025Estimated Fair Value
Financial AssetsCarrying AmountLevel 1Level 2Level 3Total
Cash and cash equivalents$499.2 $499.2 $— $— $499.2 
Short-term investments351.3 351.4 — — 351.4 
Financial Liabilities
Debt, current and long-term
$3,785.2 
(1)
$— $3,786.5 $— $3,786.5 

(1)The carrying amount of debt excluded a $1.7 million long-term finance lease obligation and $5.5 million of unamortized debt issuance costs.
Schedule of Fair Value, Assets and Liabilities Measured on Recurring Basis
The estimated fair values of the Company's financial assets and liabilities which were accounted for at fair value on a recurring basis in periods subsequent to initial recognition on the Condensed Consolidated Balance Sheets, were as follows (in millions):

As of September 30, 2026Estimated Fair Value
Financial AssetsLevel 1Level 2Level 3
Effect of netting
and cash margin
receivables (1)
Total
     Forward natural gas contracts (2)
$— $67.8 $— $(4.2)$63.6 
     NYMEX/ICE natural gas contracts11.5 — — (11.5)— 
          Total$11.5 $67.8 $— $(15.7)$63.6 
Financial Liabilities
     Forward natural gas contracts (3)
$— $24.7 $— $(4.2)$20.5 
     NYMEX/ICE natural gas contracts
18.1 — — (18.1)— 
          Total
$18.1 $24.7 $— $(22.3)$20.5 

(1)Reflects $6.6 million of cash margin receivables offset with derivative instruments.
(2)$62.3 million were recorded in Derivative Assets (current portion) and $1.3 million were recorded in Other Assets (noncurrent portion).
(3)$13.8 million were recorded in Other Current Liabilities (current portion) and $6.7 million were recorded in Other Liabilities (noncurrent portion).