v3.25.1
Derivative Instruments (Tables)
 3 Months Ended
Mar. 31, 2025
Derivative Instruments and Hedging Activities Disclosure [Abstract]  
Schedule of Notional Volume of Natural Gas Derivatives That is Expected to Settle or Mature Each Year
The following table reflects the notional volume of our natural gas derivatives as of March 31, 2025 that is expected to settle or mature each year:
Year
 Natural Gas Swaps
(MMBTUs)
 (in millions)
202521.9 
202623.0 
202712.7 
20284.4 
20293.7 
20302.5 
Total68.2 
Schedule of Fair Value of Derivative Instruments and Effect on Consolidated Balance Sheets
The table below reflects the fair value of derivative instruments subject to the right of setoff and their effect on our consolidated balance sheets at March 31, 2025 and December 31, 2024. We have elected to offset the recognized fair value amounts for multiple derivative instruments executed with the same counterparty in our financial statements when a legal right of setoff exists.
Consolidated Balance Sheet
Location		Fair Value
20252024
AssetsLiabilitiesNet Carrying Value Presented on the Balance SheetAssetsLiabilitiesNet Carrying Value Presented on the Balance Sheet
Assets(dollars in thousands)
Natural gas swapsOther current assets$42,157 $(59)$42,098 $19,527 $(1,563)$17,964 
Natural gas swapsOther deferred charges22,065 (4,371)17,694 17,566 (5,279)12,287 
Liabilities
Natural gas swapsOther current liabilities$— $— $— $290 $(1,917)$(1,627)
Natural gas swapsOther deferred credits— — — — — — 
Total$64,222 $(4,430)$59,792 $37,383 $(8,759)$28,624 
Schedule of The Realized Gains and (losses) on Derivative Instruments Recognized in Margin
The following table presents the gross realized gains and (losses) on derivative instruments recognized in net margins for the three months ended March 31, 2025 and 2024.
Statement of Revenues and Expenses
Location		Three Months Ended March 31,
 20252024
 (dollars in thousands)
Natural gas swaps gainsFuel$2,366 $41 
Natural gas swaps lossesFuel(1,359)(8,452)
Total $1,007 $(8,411)
Schedule of Unrealized Gains on Derivative Instruments Deferred on The Balance Sheet
The following table presents the unrealized gains on derivative instruments deferred on the balance sheet at March 31, 2025 and December 31, 2024.
Balance Sheet Location20252024
 (dollars in thousands)
Natural gas swapsRegulatory liability$59,792 $28,624 
Total $59,792 $28,624