Fair Value Measurements (Details) - USD ($) $ in Thousands	Sep. 30, 2023	Dec. 31, 2022
Assets and liabilities subject to fair value measurements
Commodity futures - financial assets	$ 6,666	$ 4,271
Commodity futures - financial liabilities	5,857	7,388
Carrying amount	3,100,000	3,100,000
Level 2
Assets and liabilities subject to fair value measurements
Fair value of long-term debt, including current maturities	2,700,000	2,700,000
Recurring
Assets and liabilities subject to fair value measurements
Short-term investments	500,844	628,215
Recurring \| Level 1
Assets and liabilities subject to fair value measurements
Short-term investments
Recurring \| Level 2
Assets and liabilities subject to fair value measurements
Short-term investments	500,844	628,215
Recurring \| Level 3
Assets and liabilities subject to fair value measurements
Short-term investments
Futures \| Recurring \| Commodity contract
Assets and liabilities subject to fair value measurements
Commodity futures - financial assets	6,666	4,271
Commodity futures - financial liabilities	5,857	7,388
Futures \| Recurring \| Level 1 \| Commodity contract
Assets and liabilities subject to fair value measurements
Commodity futures - financial assets
Commodity futures - financial liabilities
Futures \| Recurring \| Level 2 \| Commodity contract
Assets and liabilities subject to fair value measurements
Commodity futures - financial assets	6,666	4,271
Commodity futures - financial liabilities	5,857	7,388
Futures \| Recurring \| Level 3 \| Commodity contract
Assets and liabilities subject to fair value measurements
Commodity futures - financial assets
Commodity futures - financial liabilities

Fair value, before effects of master netting arrangements, of a financial asset or other contract with one or more underlyings, notional amount or payment provision or both, and the contract can be net settled by means outside the contract or delivery of an asset. Includes assets elected not to be offset. Excludes assets not subject to a master netting arrangement.

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Amount, after deduction of unamortized premium (discount) and debt issuance cost, of long-term debt. Excludes lease obligation.

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