v3.8.0.1

DERIVATIVES AND RISK MANAGEMENT ACTIVITIES (Tables) | 12 Months Ended
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Dec. 31, 2017
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Text Block] | The fair values of our derivative instruments included in our consolidated balance sheets were as follows:
|  |  | Asset Derivatives |  | Liability Derivatives
| Balance Sheet Location |  | December 31,
|  | 2017 |  | 2016 |  | 2017 |  | 2016
|  |  | (Thousands of Dollars)
Derivatives Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |
Interest rate swaps | Other long-term assets, net |  | $ | — |  |  | $ | 1,314 |  |  | $ | — |  |  | $ | — |
Commodity contracts | Accrued liabilities |  | — |  |  | 144 |  |  | (112 | ) |  | (3,566 | )
Interest rate swaps | Accrued liabilities |  | — |  |  | — |  |  | (5,394 | ) |  | — |
Interest rate swaps | Other long-term liabilities |  | — |  |  | — |  |  | (4,594 | ) |  | (2,632 | )
Total |  |  | — |  |  | 1,458 |  |  | (10,100 | ) |  | (6,198 | )
Derivatives Not Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |
Commodity contracts | Other current assets |  | — |  |  | 265 |  |  | — |  |  | (110 | )
Commodity contracts | Accrued liabilities |  | 742 |  |  | 9,128 |  |  | (1,508 | ) |  | (10,758 | )
Total |  |  | 742 |  |  | 9,393 |  |  | (1,508 | ) |  | (10,868 | )
Total Derivatives |  |  | $ | 742 |  |  | $ | 10,851 |  |  | $ | (11,608 | ) |  | $ | (17,066 | )
Offsetting Assets [Table Text Block] | The following are the net amounts presented on the consolidated balance sheets:
|  | December 31,
Commodity Contracts |  | 2017 |  | 2016
|  | (Thousands of Dollars)
Net amounts of assets presented in the consolidated balance sheets |  | $ | — |  |  | $ | 155 |
Net amounts of liabilities presented in the consolidated balance sheets |  | $ | (878 | ) |  | $ | (5,052 | )
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Text Block] | We recognize the impact of our commodity contracts on earnings in “Cost of product sales” on the consolidated income statements, and that impact was as follows:
|  | Year Ended December 31,
|  | 2017 |  | 2016 |  | 2015
|  | (Thousands of Dollars)
Derivatives Designated as Fair Value Hedging Instruments: |  |  |  |  |  |
Gain (loss) recognized in income on derivative |  | $ | 806 |  |  | $ | (11,254 | ) |  | $ | 21,589 |
(Loss) gain recognized in income on hedged item |  | (656 | ) |  | 15,295 |  |  | (18,047 | )
Gain recognized in income for ineffective portion |  | $ | 150 |  |  | $ | 4,041 |  |  | $ | 3,542 |
Derivatives Not Designated as Hedging Instruments: |  |  |  |  |  |
(Loss) gain recognized in income on derivative |  | $ | (668 | ) |  | $ | 225 |  |  | $ | 2,208 |
Our interest rate swaps had the following impact on earnings:
|  | Year Ended December 31,
|  | 2017 |  | 2016 |  | 2015
|  | (Thousands of Dollars)
Derivatives Designated as Cash Flow Hedging Instruments: |  |  |  |  |  |
(Loss) gain recognized in other comprehensive (loss) income on derivative (effective portion) |  | $ | (8,670 | ) |  | $ | (2,621 | ) |  | $ | 1,303 |
Loss reclassified from AOCI into interest expense, net (effective portion) |  | (6,624 | ) |  | (8,331 | ) |  | (9,802 | )

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- Definition Tabular disclosure of derivative and other financial assets that are subject to offsetting, including master netting arrangements. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225862-175312 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 20 -Section 50 -Paragraph 4 -URI http://asc.fasb.org/extlink&oid=51824906&loc=SL20225877-175312 + Details
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- Definition Tabular disclosure of the location and amount of derivative instruments and nonderivative instruments designated as hedging instruments reported before netting adjustments, and the amount of gain (loss) on derivative instruments and nonderivative instruments designated and qualified as hedging instruments. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624171-113959 Reference 2: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5618551-113959 + Details
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