v3.10.0.1

DERIVATIVES AND RISK MANAGEMENT ACTIVITIES (Tables) | 6 Months Ended
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Jun. 30, 2018
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of Derivative Instruments in Statement of Financial Position, Fair Value [Table 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 |  | June 30, 2018 |  | December 31, 2017 |  | June 30, 2018 |  | December 31, 2017
|  |  | (Thousands of Dollars)
Derivatives Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |
Interest rate swaps | Other long-term assets, net |  | $ | 4,491 |  |  | $ | — |  |  | $ | — |  |  | $ | — |
Commodity contracts | Accrued liabilities |  | — |  |  | — |  |  | (70 | ) |  | (112 | )
Interest rate swaps | Accrued liabilities |  | — |  |  | — |  |  | — |  |  | (5,394 | )
Interest rate swaps | Other long-term liabilities |  | — |  |  | — |  |  | — |  |  | (4,594 | )
Total |  |  | 4,491 |  |  | — |  |  | (70 | ) |  | (10,100 | )
Derivatives Not Designated as Hedging Instruments: |  |  |  |  |  |  |  |  |
Commodity contracts | Accrued liabilities |  | 1,278 |  |  | 742 |  |  | (1,455 | ) |  | (1,508 | )
Total Derivatives |  |  | $ | 5,769 |  |  | $ | 742 |  |  | $ | (1,525 | ) |  | $ | (11,608 | )
Derivatives Assets And Liabilities Eligible for Offset Net [Table Text Block] | The following are the net amounts presented on the consolidated balance sheets:
Commodity Contracts |  | June 30, 2018 |  | December 31, 2017
|  | (Thousands of Dollars)
Net amounts of assets presented in the consolidated balance sheets |  | $ | — |  |  | $ | — |
Net amounts of liabilities presented in the consolidated balance sheets |  | $ | (247 | ) |  | $ | (878 | )
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 condensed consolidated statements of comprehensive income, as follows:
| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2018 |  | 2017 |  | 2018 |  | 2017
| (Thousands of Dollars)
Derivatives Designated as Fair Value Hedging Instruments: |  |  |  |  |  |  |
(Loss) gain recognized in income on derivative | $ | (1,007 | ) |  | $ | 364 |  |  | $ | (1,303 | ) |  | $ | 2,461 |
Gain (loss) recognized in income on hedged item | 981 |  |  | (313 | ) |  | 1,218 |  |  | (2,147 | )
(Loss) gain recognized in income for ineffective portion | $ | (26 | ) |  | $ | 51 |  |  | $ | (85 | ) |  | $ | 314 |
Derivatives Not Designated as Hedging Instruments: |  |  |  |  |  |  |
(Loss) gain recognized in income on derivative | $ | (90 | ) |  | $ | 52 |  |  | $ | (231 | ) |  | $ | (86 | )
Our interest rate swaps had the following impact on earnings:
| Three Months Ended June 30, |  | Six Months Ended June 30,
| 2018 |  | 2017 |  | 2018 |  | 2017
| (Thousands of Dollars)
Derivatives Designated as Cash Flow Hedging Instruments: |  |  |  |  |  |  |
Gain (loss) recognized in other comprehensive income on derivative (effective portion) | $ | 5,106 |  |  | $ | (7,980 | ) |  | $ | 22,527 |  |  | $ | (7,941 | )
Loss reclassified from AOCI into interest expense, net (effective portion) | $ | (1,162 | ) |  | $ | (1,729 | ) |  | $ | (2,552 | ) |  | $ | (3,528 | )

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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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- Definition Tabular disclosure of the location and fair value amounts of derivative instruments (and nonderivative instruments that are designated and qualify as hedging instruments) reported in the statement of financial position. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4B -URI http://asc.fasb.org/extlink&oid=84234895&loc=SL5624163-113959 + Details
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