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Derivative Instruments and Hedging Activities - Narrative (Details) - Not Designated as Hedging Instrument - Commodity swaps
gal in Millions
1 Months Ended 3 Months Ended 12 Months Ended
Oct. 31, 2018
contract
gal
Mar. 31, 2020
$ / gal
gal
Dec. 31, 2019
$ / gal
gal
Derivative [Line Items]      
Derivative asset, number of instruments held | contract 2    
Volumes (Diesel Gallons) | gal 5.0 20.6 21.9
Weighted -average price per diesel gallon (in usd per gallon) | $ / gal   2.25 2.30