Derivative Accounting - Derivative Instruments in the Balance Sheets (Details) - Commodity Contracts - USD ($) $ in Thousands	Mar. 31, 2024	Dec. 31, 2023
Assets
Gross recognized derivatives	$ 73	$ 8,497
Amounts offset	0	(1,694)
Net Recognized Derivatives	73	6,803
Other	5	5
Amounts Reported on Balance Sheets	78	6,808
Liabilities
Gross recognized derivatives	(154,731)	(128,711)
Amounts offset	13,100	10,894
Net Recognized Derivatives	(141,631)	(117,817)
Other	(6,771)	(6,071)
Amounts Reported on Balance Sheets	(148,402)	(123,888)
Assets and Liabilities
Gross recognized derivatives	(154,658)	(120,214)
Amounts offset	13,100	9,200
Net Recognized Derivatives	(141,558)	(111,014)
Other	(6,766)	(6,066)
Amounts Reported on Balance Sheets	(148,324)	(117,080)
Cash collateral received subject to offsetting	13,100
Cash collateral received from counterparties	6,771	6,071
Current assets
Assets
Gross recognized derivatives	73	8,497
Amounts offset	0	(1,694)
Net Recognized Derivatives	73	6,803
Other	5	5
Amounts Reported on Balance Sheets	78	6,808
Investments and other assets
Assets
Gross recognized derivatives	0	0
Amounts offset	0	0
Net Recognized Derivatives	0	0
Other	0	0
Amounts Reported on Balance Sheets	0	0
Current liabilities
Liabilities
Gross recognized derivatives	(119,859)	(85,736)
Amounts offset	13,100	10,894
Net Recognized Derivatives	(106,759)	(74,842)
Other	(6,771)	(6,071)
Amounts Reported on Balance Sheets	(113,530)	(80,913)
Assets and Liabilities
Cash collateral received from counterparties	6,771	6,071
Deferred credits and other
Liabilities
Gross recognized derivatives	(34,872)	(42,975)
Amounts offset	0	0
Net Recognized Derivatives	(34,872)	(42,975)
Other	0	0
Amounts Reported on Balance Sheets	(34,872)	(42,975)
Assets and Liabilities
Cash collateral received from counterparties	$ 0	$ 0