Fair Value - Schedule of Fair Value of Assets and Liabilities Measured on Recurring Basis (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gross Asset	$ 74,665	$ 36,581
Liability	46,146	74,940
Fair Value, Recurring [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	31,278	13,460
Financial Liabilities Fair Value Disclosure	6,739	33,327
Counterparty and Cash Collateral Netting, Assets	(52,077)	(32,524)
Counterparty and Cash Collateral Netting, Liabilities	(39,407)	(41,613)
Fair Value, Recurring [Member] \| Fixed Income Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation assets:	1,658	1,809
Fair Value, Recurring [Member] \| Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation assets:	7,032	7,594
Fair Value, Recurring [Member] \| Energy Commodity Derivatives [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Counterparty and Cash Collateral Netting, Assets	(51,898)	(31,211)
Derivative Asset	18,641	2,908
Counterparty and Cash Collateral Netting, Liabilities	(39,228)	(40,300)
Derivative Liability	542	1,433
Fair Value, Recurring [Member] \| Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Counterparty and Cash Collateral Netting, Assets		(1,170)
Derivative Asset	3,801	1,149
Counterparty and Cash Collateral Netting, Liabilities		(1,170)
Derivative Liability		24,104
Fair Value, Recurring [Member] \| Natural Gas Exchange Agreements [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Counterparty and Cash Collateral Netting, Assets	(179)	(143)
Counterparty and Cash Collateral Netting, Liabilities	(179)	(143)
Derivative Liability	6,197	7,771
Fair Value, Recurring [Member] \| Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Derivative Asset	146
Derivative Liability		19
Fair Value, Recurring [Member] \| Level 1 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	8,690	9,403
Fair Value, Recurring [Member] \| Level 1 [Member] \| Fixed Income Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation assets:	1,658	1,809
Fair Value, Recurring [Member] \| Level 1 [Member] \| Equity Funds [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Deferred compensation assets:	7,032	7,594
Fair Value, Recurring [Member] \| Level 2 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	74,486	36,438
Financial Liabilities Fair Value Disclosure	39,770	67,026
Fair Value, Recurring [Member] \| Level 2 [Member] \| Energy Commodity Derivatives [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gross Asset	70,539	34,119
Liability	39,770	41,733
Fair Value, Recurring [Member] \| Level 2 [Member] \| Interest Rate Swap [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gross Asset	3,801	2,319
Liability		25,274
Fair Value, Recurring [Member] \| Level 2 [Member] \| Foreign Exchange Contract [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gross Asset	146
Liability		19
Fair Value, Recurring [Member] \| Level 3 [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Assets, Fair Value Disclosure	179	143
Financial Liabilities Fair Value Disclosure	6,376	7,914
Fair Value, Recurring [Member] \| Level 3 [Member] \| Natural Gas Exchange Agreements [Member]
Fair Value, Balance Sheet Grouping, Financial Statement Captions [Line Items]
Gross Asset	179	143
Liability	$ 6,376	$ 7,914

Fair value portion of probable future economic benefits obtained or controlled by an entity as a result of past transactions or events.

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Fair value of liability associated with 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, and obligation to return cash collateral under master netting arrangements.

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Fair value, after the 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 not subject to a master netting arrangement and not elected to be offset.

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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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Fair value, before effects of master netting arrangements, of a financial liability or 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 liabilities elected not to be offset. Excludes liabilities not subject to a master netting arrangement.

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Fair value of asset associated with financial liability or 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, and right to receive cash collateral under master netting arrangements.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Fair value of financial obligations, including, but not limited to, debt instruments, derivative liabilities, federal funds purchased and sold under agreements to repurchase, securities loaned or sold under agreements to repurchase, financial instruments sold not yet purchased, guarantees, line of credit, loans and notes payable, servicing liability, and trading liabilities.

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Fair value portion of investment securities, including, but not limited to, marketable securities, derivative financial instruments, and investments accounted for under the equity method.

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