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MULTI-EMPLOYER WITHDRAWAL LIABILITIES (Tables) | 12 Months Ended
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Dec. 31, 2020
MULTI-EMPLOYER WITHDRAWAL LIABILITIES |
Schedule of future estimated annual payments to the multi-employer pension plan | ​
​ | ​ | ​ | ​
Year (in millions) | ​ | Total
2021 |  | $ | 4.1
2022 | ​ | ​ | 4.1
2023 | ​ | ​ | 4.1
2024 | ​ | ​ | 4.1
2025 | ​ | ​ | 4.1
Thereafter | ​ | ​ | 59.7
Total remaining future undiscounted payments due to the ILA-PRSSA pension fund | ​ | ​ | 80.2
Less: amount representing interest | ​ | ​ | (23.3)
Present value of multi-employer withdrawal liability | ​ | ​ | 56.9
Current portion of multi-employer withdrawal liability (see Note 2) | ​ | ​ | (4.1)
Long-term portion of multi-employer withdrawal liability (see Note 2) |  | $ | 52.8

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- Definition Schedule of future estimated annual cash payments information related to multiemployer plans in which the employer participates. A multiemployer plan is a pension or postretirement benefit plan to which two or more unrelated employers contribute where assets contributed by one participating employer may be used to provide benefits to employees of other participating employers. + References No definition available. + Details
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- References No definition available. + Details
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