v3.20.2

Equity compensation plans (Tables) | 6 Months Ended
--- | ---
Jun. 30, 2020
Equity compensation plans |
Schedule of changes in outstanding LTIP notional units | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | ​ | ​
​ | ​ | ​ | ​ | ​ | ​ | ​ | Grant Date |
​ | ​ | ​ | ​ | ​ | ​ | ​ | Weighted-Average |
​ |  | Notional Shares | ​ | ​ | ​ | ​ | Fair Value per Notional Share |
Outstanding at December 31, 2019 |  | 3,578,092 | ​ | ​ | ​ | $ | 2.38 | ​
Granted |  | 1,866,748 | ​ | ​ | ​ | ​ | 2.49 | ​
Vested and redeemed |  | (1,702,571) | ​ | ​ | ​ | ​ | 2.34 | ​
Forfeitures |  | (23,388) | ​ | ​ | ​ | ​ | 2.40 | ​
Outstanding at June 30, 2020 |  | 3,718,881 | ​ | ​ | ​ | $ | 2.45 | ​

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