PENSION BENEFITS - Components of net periodic benefit (credit) expense (Details) - Pension Plan - USD ($) $ in Thousands |
3 Months Ended | 6 Months Ended | 12 Months Ended | |||
|---|---|---|---|---|---|---|
Mar. 31, 2021 |
Mar. 31, 2020 |
Dec. 31, 2020 |
Jun. 25, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
| Defined Benefit Plan Disclosure | ||||||
| Service cost | $ 16 | $ 14 | $ 94 | $ 41 | $ 692 | $ 864 |
| Interest cost | 259 | 51 | 545 | 593 | 1,410 | 1,320 |
| Expected return on plan assets | (399) | 0 | (783) | (817) | (1,462) | (1,507) |
| Recognized actuarial loss | 9 | 40 | 0 | 276 | 1,332 | 1,344 |
| Net periodic benefit (credit) cost | $ (115) | $ 105 | $ (169) | $ 126 | $ 2,438 | $ 2,170 |
| X | ||||||||||
- Definition Amount of gain (loss) recognized in net periodic benefit (cost) credit of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. No definition available.
|
| X | ||||||||||
- Definition Amount of expected return (loss) recognized in net periodic benefit (cost) credit, calculated based on expected long-term rate of return and market-related value of plan assets of defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of cost recognized for passage of time related to defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of net periodic benefit cost (credit) for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of cost for actuarial present value of benefits attributed to service rendered by employee for defined benefit plan. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Details
|