v3.10.0.1

FAIR VALUE MEASUREMENTS (Tables) | 9 Months Ended
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Sep. 30, 2018
Fair Value Disclosures [Abstract] |
Fair Value Measurements, Recurring and Nonrecurring [Table Text Block] | The following assets and liabilities are measured at fair value on a recurring basis:
| September 30, 2018
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Assets: |  |  |  |  |  |  |
Other long-term assets, net: |  |  |  |  |  |  |
Interest rate swaps | $ | — |  |  | $ | 8,031 |  |  | $ | — |  |  | $ | 8,031 |
Liabilities: |  |  |  |  |  |  |
Accrued liabilities: |  |  |  |  |  |  |
Commodity derivatives | $ | (276 | ) |  | $ | — |  |  | $ | — |  |  | $ | (276 | )
| December 31, 2017
| Level 1 |  | Level 2 |  | Level 3 |  | Total
| (Thousands of Dollars)
Assets: |  |  |  |  |  |  |
Other current assets: |  |  |  |  |  |  |
Product imbalances | $ | 3,890 |  |  | $ | — |  |  | $ | — |  |  | $ | 3,890 |
Liabilities: |  |  |  |  |  |  |
Accrued liabilities: |  |  |  |  |  |  |
Product imbalances | $ | (1,534 | ) |  | $ | — |  |  | $ | — |  |  | $ | (1,534 | )
Commodity derivatives | (878 | ) |  | — |  |  | — |  |  | (878 | )
Interest rate swaps | — |  |  | (5,394 | ) |  | — |  |  | (5,394 | )
Other long-term liabilities: |  |  |  |  |  |  |
Interest rate swaps | — |  |  | (4,594 | ) |  | — |  |  | (4,594 | )
Total liabilities | $ | (2,412 | ) |  | $ | (9,988 | ) |  | $ | — |  |  | $ | (12,400 | )
Fair Value and Carrying Value of Debt and Note Receivable [Table Text Block] | The estimated fair values and carrying amounts of long-term debt, including the current portion, were as follows:
| September 30, 2018 |  | December 31, 2017
| (Thousands of Dollars)
Fair value | $ | 3,409,199 |  |  | $ | 3,677,622 |
Carrying amount | $ | 3,376,852 |  |  | $ | 3,613,059 |

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- Definition Tabular disclosure of financial instruments measured at fair value, including those classified in shareholders' equity measured on a recurring or nonrecurring basis. Disclosures include, but are not limited to, fair value measurements recorded and the reasons for the measurements, level within the fair value hierarchy in which the fair value measurements are categorized and transfers between levels 1 and 2. Nonrecurring fair value measurements are those that are required or permitted in the statement of financial position in particular circumstances. + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 3 -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19279-110258 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2C -URI http://asc.fasb.org/extlink&oid=99377789&loc=SL7498348-110258 Reference 4: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 1 -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19190-110258 Reference 5: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (a) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 Reference 6: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 820 -SubTopic 10 -Section 50 -Paragraph 2 -Subparagraph (bb) -URI http://asc.fasb.org/extlink&oid=99377789&loc=d3e19207-110258 + Details
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- Definition Tabular disclosure of information pertaining to carrying amount and estimated fair value of short-term and long-term debt instruments or arrangements, including but not limited to, identification of terms, features, and collateral requirements. + References No definition available. + Details
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