BASIS OF PRESENTATION - Other Expense (Income) (Details) - USD ($) $ in Millions |
3 Months Ended | 6 Months Ended | ||
|---|---|---|---|---|
Jun. 30, 2021 |
Jun. 30, 2020 |
Jun. 30, 2021 |
Jun. 30, 2020 |
|
| BASIS OF PRESENTATION | ||||
| Derivative liability fair value adjustment for embedded conversion feature in the Convertible Notes due 2024 | $ (0.5) | |||
| Derivative asset fair value adjustment for contingent call option related to the Class B common stock purchase and cancellation agreement | $ (6.4) | 13.7 | ||
| Credit losses (income) related to contingent lease guarantees | $ (3.7) | 3.9 | $ (5.7) | 9.2 |
| Governmental assistance due to COVID-19- International markets | (42.2) | (4.4) | (50.4) | (4.4) |
| Governmental assistance due to COVID-19 - Domestic markets | (4.2) | |||
| Foreign currency transaction (gains) losses | 3.4 | (2.1) | (0.4) | (0.1) |
| Non-operating components of net periodic benefit cost (income) | (0.2) | 0.1 | (0.4) | 0.1 |
| Financing fees related to modification of debt | 2.8 | 1.0 | 2.8 | |
| Other | (0.5) | (0.5) | ||
| Total other expense (income) | $ (42.7) | $ (6.6) | $ (60.1) | $ 20.3 |