Derivatives (Net Derivatives As Reflected On The Balance Sheets) (Details) - USD ($) $ in Thousands	Mar. 31, 2022	Dec. 31, 2021
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ (4,291)	$ 3,901
Current asset representing cash collateral posted	2,600	2,800
Heating oil and coal \| Other current assets
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	8,547	4,214
Coal Contract \| Accrued expenses and other current liabilities
Derivatives, Fair Value [Line Items]
Net derivatives as classified in the balance sheet	$ (12,838)	$ (313)

Amount of obligation to return cash collateral under master netting arrangements that have not been offset against derivative assets.

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-Publisher FASB
-Name Accounting Standards Codification
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Data Type:	xbrli:monetaryItemType
Balance Type:	credit
Period Type:	instant