FAIR VALUE MEASUREMENTS (Measured on Recurring Basis) (Details) (Fair Value, Measurements, Recurring [Member], USD $) | Sep. 30, 2014 | Dec. 31, 2013 |
In Thousands, unless otherwise specified |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Marketable securities | $264,913 | ' |
Non-qualified pension plan assets | 5,468 | 4,905 |
Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Marketable securities | 264,913 | ' |
Non-qualified pension plan assets | 5,468 | 4,905 |
Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Marketable securities | 0 | ' |
Non-qualified pension plan assets | 0 | 0 |
Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Marketable securities | 0 | ' |
Non-qualified pension plan assets | 0 | 0 |
Catalyst lease obligations [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Catalyst lease obligations | 39,325 | 53,089 |
Catalyst lease obligations [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Catalyst lease obligations | 0 | 0 |
Catalyst lease obligations [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Catalyst lease obligations | 39,325 | 53,089 |
Catalyst lease obligations [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Catalyst lease obligations | 0 | 0 |
Commodity contract [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative liability, gross carrying value | 234,403 | ' |
Derivative liability, effect of counter-party netting | -232,671 | ' |
Derivative Liability | 1,732 | 30,354 |
Commodity contract [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative liability, gross carrying value | 228,141 | ' |
Derivative Liability | ' | 0 |
Commodity contract [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative liability, gross carrying value | 6,262 | ' |
Derivative Liability | ' | 6,989 |
Commodity contract [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative liability, gross carrying value | 0 | ' |
Derivative Liability | ' | 23,365 |
Derivatives included with inventory supply arrangement obligations [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 1,482 | ' |
Derivative assets, effect of counter-party netting | 0 | ' |
Derivative assets, net carrying value | 1,482 | ' |
Derivative Liability | ' | 177 |
Derivatives included with inventory supply arrangement obligations [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 0 | ' |
Derivative Liability | ' | 0 |
Derivatives included with inventory supply arrangement obligations [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 1,482 | ' |
Derivative Liability | ' | 177 |
Derivatives included with inventory supply arrangement obligations [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 0 | ' |
Derivative Liability | ' | 0 |
Money market funds [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 5,557 | 5,857 |
Money market funds [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 5,557 | 5,857 |
Money market funds [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 0 | 0 |
Money market funds [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Cash and cash equivalents | 0 | 0 |
Commodity contract [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 284,684 | ' |
Derivative assets, effect of counter-party netting | -232,671 | ' |
Derivative assets, net carrying value | 52,013 | 10,933 |
Commodity contract [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 261,041 | ' |
Derivative assets, net carrying value | ' | 4,252 |
Commodity contract [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 10,597 | ' |
Derivative assets, net carrying value | ' | 6,681 |
Commodity contract [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 13,046 | ' |
Derivative assets, net carrying value | ' | 0 |
Derivatives included with intermediation agreement obligations [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 35,959 | ' |
Derivative assets, effect of counter-party netting | 0 | ' |
Derivative assets, net carrying value | 35,959 | 6,016 |
Derivatives included with intermediation agreement obligations [Member] | Level 1 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 0 | ' |
Derivative assets, net carrying value | ' | 0 |
Derivatives included with intermediation agreement obligations [Member] | Level 2 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 35,959 | ' |
Derivative assets, net carrying value | ' | 6,016 |
Derivatives included with intermediation agreement obligations [Member] | Level 3 [Member] | ' | ' |
Fair Value, Assets and Liabilities Measured on Recurring and Nonrecurring Basis [Line Items] | ' | ' |
Derivative assets, gross carrying value | 0 | ' |
Derivative assets, net carrying value | ' | $0 |