v3.20.2

DERIVATIVES AND FAIR VALUE MEASUREMENTS (Tables) | 6 Months Ended
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Jun. 30, 2020
Derivative Instruments and Hedging Activities Disclosure [Abstract] |
Schedule of Derivative Instruments, Gain (Loss) in Statement of Financial Performance [Text Block] | Our forward-starting interest rate swaps had the following impact on earnings:
| Three Months Ended June 30, |  |  |  | Six Months Ended June 30, |  |
| 2020 |  | 2019 |  | 2020 |  | 2019
| (Thousands of Dollars) |  |  |  |  |  |
Loss recognized in other comprehensive income (loss) on derivative | $ | (461) |  |  | $ | (9,784) |  |  | $ | (30,291) |  |  | $ | (16,592) |
Loss reclassified from AOCI into interest expense, net | $ | (878) |  |  | $ | (1,005) |  |  | $ | (1,525) |  |  | $ | (2,083) |
Fair Value and Carrying Value of Debt [Table Text Block] | The estimated fair values and carrying amounts of long-term debt, including the current portion and excluding finance leases, were as follows:
| June 30, 2020 |  | December 31, 2019
| (Thousands of Dollars) |  |
Fair value | $ | 3,372,527 |  |  | $ | 3,442,001 |
Carrying amount | $ | 3,374,056 |  |  | $ | 3,331,839 |

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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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- 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/disclosureRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4E -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624181-113959 Reference 2: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4A -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5618551-113959 Reference 3: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 815 -SubTopic 10 -Section 50 -Paragraph 4C -URI http://asc.fasb.org/extlink&oid=109980867&loc=SL5624171-113959 + Details
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