LEASE OBLIGATIONS - Other information (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
| Leases [Abstract] | Ìý | Ìý | Ìý |
| Operating Lease, Payments | $ 43 | $ 4 | Ìý |
| Finance Lease, Interest Payment on Liability | 4 | 2 | Ìý |
| Finance Lease, Principal Payments | 15 | 6 | Ìý |
| Right-of-use asset - finance leases | $ 44 | $ 29 | $ 8 |
| Operating Lease, Weighted Average Remaining Lease Term | 8 years | 10 years | Ìý |
| Finance Lease, Weighted Average Remaining Lease Term | 5 years | 6 years | Ìý |
| Operating Lease, Weighted Average Discount Rate, Percent | 8.00% | 8.00% | Ìý |
| Finance Lease, Weighted Average Discount Rate, Percent | 4.00% | 5.00% | Ìý |
| X | ||||||||||
- Definition Amount of interest paid on finance lease liability. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Amount of cash outflow for principal payment on finance lease. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average discount rate for finance lease calculated at point in time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average remaining lease term for finance lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- References No definition available.
|
| X | ||||||||||
- Definition Amount of cash outflow from operating lease, excluding payments to bring another asset to condition and location necessary for its intended use. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average discount rate for operating lease calculated at point in time. Reference 1: http://www.xbrl.org/2003/role/disclosureRef
|
| X | ||||||||||
- Definition Weighted average remaining lease term for operating lease, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents reported fact of one year, five months, and thirteen days. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|
| X | ||||||||||
- Definition Amount of increase in right-of-use asset obtained in exchange for finance lease liability. Reference 1: http://www.xbrl.org/2003/role/exampleRef
|