v2.4.0.6

FAIR VALUE MEASUREMENTS (Tables) | 9 Months Ended
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Sep. 30, 2012
FAIR VALUE MEASUREMENTS [Abstract] |
Fair Value, Measurement Inputs, Disclosure [Text Block] | The following assets and liabilities are measured at fair value:
| September 30, 2012
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 898 |  |  | $ | — |  |  | $ | — |  |  | $ | 898 |
Commodity derivatives | 19,013 |  |  | 2,365 |  |  | — |  |  | 21,378 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 6,675 |  |  | — |  |  | 6,675 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (577 | ) |  | — |  |  | — |  |  | (577 | )
Commodity derivatives | (5,929 | ) |  | (20,861 | ) |  | — |  |  | (26,790 | )
Interest rate swaps | — |  |  | (41,117 | ) |  | — |  |  | (41,117 | )
Other long-term liabilities: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | (1,265 | ) |  | — |  |  | (1,265 | )
Total | $ | 13,405 |  |  | $ | (54,203 | ) |  | $ | — |  |  | $ | (40,798 | )
| December 31, 2011
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 2,117 |  |  | $ | — |  |  | $ | — |  |  | $ | 2,117 |
Commodity derivatives | 10,282 |  |  | 1,830 |  |  | — |  |  | 12,112 |
Other long-term assets, net: |  |  |  |  |  |  |
Commodity derivatives | — |  |  | 27,084 |  |  | — |  |  | 27,084 |
Interest rate swaps | — |  |  | 2,335 |  |  | — |  |  | 2,335 |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | (1,469 | ) |  | — |  |  | — |  |  | (1,469 | )
Commodity derivatives | (5,424 | ) |  | — |  |  | — |  |  | (5,424 | )
Interest rate swaps | — |  |  | (22,009 | ) |  | — |  |  | (22,009 | )
Other long-term liabilities: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | (27,190 | ) |  | — |  |  | (27,190 | )
Total | $ | 5,506 |  |  | $ | (17,950 | ) |  | $ | — |  |  | $ | (12,444 | )
Fair Value and Carrying Value of Debt [Text Block] | The estimated fair value and carrying amount of our debt was as follows:
| September 30, 2012 |  | December 31, 2011
| (Thousands of Dollars)
Fair value | $ | 2,018,993 |  |  | $ | 2,377,565 |
Carrying amount | $ | 2,036,406 |  |  | $ | 2,293,030 |

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- Definition The entire disclosure of the fair value measurement of assets and liabilities, which includes financial instruments measured at fair value that are classified in shareholders' equity, which may be measured on a recurring or nonrecurring basis. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19279-110258 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19190-110258 Reference 3: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 33 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 4: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -URI http://asc.fasb.org/extlink&oid=7578670&loc=d3e19207-110258 Reference 5: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 32 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 6: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 107 -Paragraph 10 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. Reference 7: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Statement of Financial Accounting Standard (FAS) -Number 157 -Paragraph 6 -Footnote 4 -LegacyDoc This reference is SUPERSEDED by the Accounting Standards Codification effective for interim and annual periods ending after September 15, 2009. This reference is included to help users transition from the previous accounting hierarchy and will be removed from future versions of this taxonomy. + Details
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