FAIR VALUE MEASUREMENTS (Measured on Recurring Basis) (Details) - Fair Value, Measurements, Recurring - USD ($) $ in Millions | Jun. 30, 2023 | Dec. 31, 2022 |
Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Defined Benefit Plan, Plan Assets, Amount | $ 18.8 | $ 18.6 |
Commodity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative liability, gross carrying value | 49.4 | 35.6 |
Derivative liability, effect of counter-party netting | (49.4) | (35.6) |
Derivative Liability | 0 | 0 |
Commodity contracts | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative liability, gross carrying value | 13.4 | 20.6 |
Commodity contracts | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative liability, gross carrying value | 36 | 11.8 |
Commodity contracts | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative liability, gross carrying value | 0 | 3.2 |
Catalyst financing arrangements | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 2.7 | 4 |
Derivative liability, effect of counter-party netting | 0 | 0 |
Catalyst financing arrangements | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Catalyst financing arrangements | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 2.7 | 4 |
Catalyst financing arrangements | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Renewable Energy Credit and Emissions Obligation | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 792.3 | 1,361.1 |
Derivative liability, effect of counter-party netting | 0 | 0 |
Renewable Energy Credit and Emissions Obligation | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Renewable Energy Credit and Emissions Obligation | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 792.3 | 1,361.1 |
Renewable Energy Credit and Emissions Obligation | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Contingent consideration obligation | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 29.4 | 147.3 |
Derivative liability, effect of counter-party netting | 0 | 0 |
Contingent consideration obligation | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Contingent consideration obligation | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 0 | 0 |
Contingent consideration obligation | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Obligations, Fair Value Disclosure | 29.4 | 147.3 |
Money market funds | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents | 130.1 | 110 |
Money market funds | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents | 130.1 | 110 |
Money market funds | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents | 0 | 0 |
Money market funds | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Cash and cash equivalents | 0 | 0 |
Commodity contracts | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 66 | 49.5 |
Derivative assets, effect of counter-party netting | (49.4) | (35.6) |
Derivative assets, net carrying value | 16.6 | 13.9 |
Commodity contracts | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 20.3 | 33.8 |
Commodity contracts | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 33.8 | 15.7 |
Commodity contracts | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 11.9 | 0 |
Derivatives included within inventory intermediation agreement obligations | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 16.6 | 25.1 |
Derivative assets, effect of counter-party netting | 0 | 0 |
Derivative assets, net carrying value | 16.6 | 25.1 |
Derivatives included within inventory intermediation agreement obligations | Level 1 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 0 | 0 |
Derivatives included within inventory intermediation agreement obligations | Level 2 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | 16.6 | 25.1 |
Derivatives included within inventory intermediation agreement obligations | Level 3 | | |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | | |
Derivative assets, gross carrying value | $ 0 | $ 0 |