v3.8.0.1

REVENUE FROM CONTRACTS WITH CUSTOMERS (Tables) | 3 Months Ended
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Mar. 31, 2018
Revenue from Contract with Customer [Abstract] |
Schedule of Adoption of New Accounting Pronouncements [Table Text Block] | The adoption of ASC Topic 606 affected our consolidated statement of comprehensive income for the three months ended March 31, 2018 as follows:
| As Reported |  | Without Adoption of ASC Topic 606 |  | Effect of Change Higher/(Lower)
| (Thousands of Dollars)
Revenues | $ | 475,881 |  |  | $ | 481,786 |  |  | $ | (5,905 | )
Operating income | $ | 98,480 |  |  | $ | 104,385 |  |  | $ | (5,905 | )
Net income | $ | 126,133 |  |  | $ | 132,038 |  |  | $ | (5,905 | )
Basic net income per common unit | $ | 1.15 |  |  | $ | 1.21 |  |  | $ | (0.06 | )
Contract with Customer, Asset and Liability [Table Text Block] | The following table provides information about contract assets and contract liabilities from contracts with customers:
| Contract Assets |  | Contract Liabilities
| (Thousands of Dollars)
Balance as of January 1, 2018 | $ | 2,127 |  |  | $ | (57,870 | )
Additions | 460 |  |  | (2,386 | )
Transfer to accounts receivable | (1,653 | ) |  | — |
Transfer to revenues | — |  |  | 2,935 |
Total activity | (1,193 | ) |  | 549 |
Balance as of March 31, 2018 | 934 |  |  | (57,321 | )
Less current portion | 749 |  |  | (13,579 | )
Noncurrent portion | $ | 185 |  |  | $ | (43,742 | )
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Table Text Block] | The following table presents our estimated revenue from contracts with customers for remaining performance obligations that has not yet been recognized, representing our contractually committed revenue as of March 31, 2018 (in thousands of dollars):
2018 (remaining) |  | $ | 377,456 |
2019 |  | 348,414 |
2020 |  | 202,526 |
2021 |  | 141,957 |
2022 |  | 105,769 |
Thereafter |  | 333,881 |
Total |  | $ | 1,510,003 |
Disaggregation of Revenue [Table Text Block] | The following table disaggregates our revenues:
| Three Months Ended March 31,
| 2018 |  | 2017
| (Thousands of Dollars)
Pipeline segment: |  |  |
Crude oil pipelines (excluding lessor revenues) | $ | 53,437 |  |  | $ | 36,747 |
Refined products and ammonia pipelines | 83,299 |  |  | 84,493 |
Total pipeline segment revenues from contracts with customers | 136,736 |  |  | 121,240 |
Lessor revenues | 54 |  |  | — |
Total pipeline segment revenues | 136,790 |  |  | 121,240 |
Storage segment: |  |  |
Throughput terminals | 20,016 |  |  | 20,690 |
Storage terminals (excluding lessor revenues) | 125,350 |  |  | 116,960 |
Total storage segment revenues from contracts with customers | 145,366 |  |  | 137,650 |
Lessor revenues | 9,962 |  |  | 9,781 |
Total storage segment revenues | 155,328 |  |  | 147,431 |
Fuels marketing segment revenues from contracts with customers | 185,838 |  |  | 222,702 |
Consolidation and intersegment eliminations: | (2,075 | ) |  | (3,943 | )
Total revenues | $ | 475,881 |  |  | $ | 487,430 |

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