v3.26.1
Fair Value Measurements - Carrying Amounts and Fair Values of Financial Instruments (Detail) - USD ($)
$ in Thousands
Jun. 30, 2026
Dec. 31, 2025
Reported Value Measurement    
Assets:    
Commodity derivatives [1] $ 123,343 $ 69,397
Marketable securities [2] 69,218 65,436
(Liabilities):    
Commodity derivatives [1] (3,387) (3,559)
Bank credit facility [3] (381,000) (118,000)
Deferred compensation plan [4] (76,102) (74,410)
Estimate of Fair Value Measurement    
Assets:    
Commodity derivatives [1] 123,343 69,397
Marketable securities [2] 69,218 65,436
(Liabilities):    
Commodity derivatives [1] (3,387) (3,559)
Bank credit facility [3] (381,000) (118,000)
Deferred compensation plan [4] (76,102) (74,410)
8.25% Senior Notes Due 2029 | Reported Value Measurement    
(Liabilities):    
Senior notes [3] 0 (600,000)
8.25% Senior Notes Due 2029 | Estimate of Fair Value Measurement    
(Liabilities):    
Senior notes [3] 0 (609,186)
4.75% Senior Notes Due 2030 | Reported Value Measurement    
(Liabilities):    
Senior notes [3] (500,000) (500,000)
4.75% Senior Notes Due 2030 | Estimate of Fair Value Measurement    
(Liabilities):    
Senior notes [3] $ (488,255) $ (493,895)
[1] Fair values for commodity derivatives utilize Level 2 inputs with the exception of swaptions and propane collars, which utilize Level 3 inputs. Fair value of swaption contracts as of June 30, 2026 was a derivative liability of $657,000 and the fair value of propane collars as of June 30, 2026 was a derivative asset of $882,000.
[2] Marketable securities, which are held in our deferred compensation plans, are actively traded on major exchanges, which is a Level 1 input.
[3] The book value of our bank debt approximates fair value because of its floating rate structure. The fair value of our senior notes is based on end of period market quotes which are Level 2 inputs. Debt is presented on the balance sheet at carrying value.
[4] The fair value of our deferred compensation plan is updated to the closing price of the marketable securities held in the plan on the balance sheet date, which is a Level 1 input.