Derivative Instruments and Hedging Activities - Notional Contracts by Derivative Type (Details) - 12 months ended Dec. 31, 2020 bbl in Thousands, MMBTU in Millions	USD ($) MMBTU bbl	XPT ( )
Derivatives designated as hedging instruments: | Natural gas price swaps - long
economic hedges by derivative type [Line Items]
Derivative nonmonetary notional amount (in MMBTUs) | MMBTU	1.8
Derivatives not designated as hedging instruments: | NYMEX futures (WTI) - short
economic hedges by derivative type [Line Items]
Derivative nonmonetary notional amount (in barrels)	160
Derivatives not designated as hedging instruments: | Forward gasoline and diesel contracts - long
economic hedges by derivative type [Line Items]
Derivative nonmonetary notional amount (in barrels)	195
Derivatives not designated as hedging instruments: | Foreign currency forward contracts
economic hedges by derivative type [Line Items]
Derivative notional amount | $	$ 418,192,532
Derivatives not designated as hedging instruments: | Forward commodity contracts (platinum)
economic hedges by derivative type [Line Items]
Derivative notional amount |		40,867