Derivatives (Narrative) (Details) - Not Designated as Hedging Instrument gal in Millions	3 Months Ended
	Mar. 31, 2022 $ / Option gal
Call Option | Heating Oil
Derivative [Line Items]
Quantities under derivative contracts (in gallons)	12
Derivative, average price risk option strike price (in used per gallon) | $ / Option	2.61
Diesel Purchases | Minimum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons)	40
Diesel Purchases | Maximum
Derivative [Line Items]
Diesel fuel purchased annually (in gallons)	45