v3.19.3.a.u2

UNIT-BASED COMPENSATION (Tables) | 12 Months Ended
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Dec. 31, 2019
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of long-term incentive plan compensation expense | The following table summarizes information pertaining to all of our long-term incentive plans:
| Units Outstanding December 31, |  | Compensation Expense Year Ended December 31,
| 2019 |  | 2018 |  | 2017 |  | 2019 |  | 2018 |  | 2017
|  |  |  |  |  |  | (Thousands of Dollars)
Restricted Units: |  |  |  |  |  |  |  |  |  |  |
Domestic employees | 1,223,143 |  |  | 1,028,484 |  |  | 736,746 |  |  | $ | 9,437 |  |  | $ | 8,233 |  |  | $ | 7,881 |
Non-employee directors (NEDs) | 61,349 |  |  | 59,752 |  |  | 27,097 |  |  | 774 |  |  | 524 |  |  | 251 |
International employees | 10,243 |  |  | 30,918 |  |  | 58,107 |  |  | 711 |  |  | 1,158 |  |  | 595 |
Performance Units | 161,561 |  |  | 158,326 |  |  | 80,961 |  |  | 4,172 |  |  | 1,889 |  |  | — |
Unit Awards | — |  |  | — |  |  | — |  |  | 22,846 |  |  | 18,895 |  |  | — |
Total | 1,456,296 |  |  | 1,277,480 |  |  | 902,911 |  |  | $ | 37,940 |  |  | $ | 30,699 |  |  | $ | 8,727 |
Restricted unit award activity | A summary of our restricted unit activity for domestic employees and, beginning January 1, 2019, NEDs is as follows:
| Number of Restricted Units |  | Weighted-Average Grant-Date Fair Value Per Unit
Nonvested units as of January 1, 2017 | 647,340 |  |  | $ | 39.72 |
Granted | 307,009 |  |  | 29.56 |
Vested | (201,466 | ) |  | 38.74 |
Forfeited | (16,137 | ) |  | 40.00 |
Nonvested units as of December 31, 2017 | 736,746 |  |  | 35.95 |
Converted on July 20, 2018 | 53,447 |  |  | 24.99 |
Granted | 518,282 |  |  | 24.07 |
Vested | (235,746 | ) |  | 35.12 |
Forfeited | (44,245 | ) |  | 36.05 |
Nonvested units as of December 31, 2018 | 1,028,484 |  |  | 29.47 |
NEDs | 59,752 |  |  | 20.93 |
Granted | 596,881 |  |  | 26.46 |
Vested | (328,386 | ) |  | 30.11 |
Forfeited | (72,239 | ) |  | 28.05 |
Nonvested units as of December 31, 2019 | 1,284,492 |  |  | 27.48 |
Performance Units [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of long-term incentive plan compensation expense | A summary of our performance units is shown below:
|  |  | Granted for Accounting Purposes
| Total Performance Units Awarded |  | Performance Units |  | Weighted-Average Grant Date Fair Value per Unit
Outstanding as of January 1, 2017 | 77,014 |  |  | 35,373 |  |  | $ | 31.75 |
Granted | 39,320 |  |  | 38,865 |  |  | 50.04 |
Performance adjustments (a) | 17,690 |  |  | 17,690 |  |  | 31.75 |
Vested | (53,063 | ) |  | (53,063 | ) |  | 31.75 |
Outstanding as of December 31, 2017 | 80,961 |  |  | 38,865 |  |  | 50.04 |
Granted | 116,230 |  |  | 80,690 |  |  | 23.43 |
Forfeitures | (38,865 | ) |  | (38,865 | ) |  | 50.04 |
Outstanding as of December 31, 2018 | 158,326 |  |  | 80,690 |  |  | 23.43 |
Granted | 95,969 |  |  | 74,439 |  |  | 28.01 |
Vested | (80,690 | ) |  | (80,690 | ) |  | 23.43 |
Forfeitures | (12,044 | ) |  | — |  |  | — |
Outstanding as of December 31, 2019 | 161,561 |  |  | 74,439 |  |  | 28.01 |
(a) Represents the additional units issued to employees resulting from performance that exceeded the specified targets for the performance measures.
Share-based Payment Arrangement [Member] |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] |
Summary of long-term incentive plan compensation expense | A summary of our unit awards is shown below:
Date of Grant |  | Grant Date Fair Value |  | Unit Awards Granted |  | Common Units Issued, Net of Employee Withholding Tax
|  | (Thousands of Dollars) |  |  |  |
February 11, 2020 |  | $ | 22,846 |  |  | 822,979 |  |  | 563,806 |
February 11, 2019 |  | $ | 17,537 |  |  | 704,886 |  |  | 482,971 |
July 23, 2018 |  | $ | 1,358 |  |  | 55,133 |  |  | 35,745 |

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