Derivative Instruments And Hedging Activities Volumes related to price risk purchase derivatives (Details) - Not Designated as Hedging Instrument [Member]	3 Months Ended
	Mar. 31, 2019 USD ($) bbl
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net | $	$ 440,629,812
Maturing in Next Twelve Months [Member]
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net | $	$ 440,629,812
NYMEX WTI Short [Member]
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Price Risk Fair Value Hedge Derivative, at Fair Value, Net	1,035,000
NYMEX WTI Short [Member] | Maturing in Next Twelve Months [Member]
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Price Risk Fair Value Hedge Derivative, at Fair Value, Net	1,035,000
Commodity Contract [Member]
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Price Risk Fair Value Hedge Derivative, at Fair Value, Net	395,000
Commodity Contract [Member] | Maturing in Next Twelve Months [Member]
Price Risk Derivatives for Future Purchases Notional Contract Volumes [Line Items]
Price Risk Fair Value Hedge Derivative, at Fair Value, Net	395,000