SEGMENT INFORMATION - NARRATIVE (Details) - USD ($) $ in Thousands	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
North America | Geographic Concentration Risk | Revenue from Contract with Customer Benchmark
Revenue, Major Customer [Line Items]
Concentration Risk, Percentage		89.00%
Operating Segments | Commodities futures and options
Revenue, Major Customer [Line Items]
Net Gain (Loss) On Commodity Derivative Positions Reclassified From Unallocated Derivative To Segment Income		$ (6,837)	$ 98,884	$ 91,026
Scenario, Forecast | Operating Segments | Commodities futures and options
Revenue, Major Customer [Line Items]
Net Gain (Loss) On Commodity Derivative Positions Reclassified From Unallocated Derivative To Segment Income	$ 39,839
Cost of Sales | Commodities futures and options
Revenue, Major Customer [Line Items]
Derivative, Gain (Loss) on Derivative, Net		$ 68,969