FAIR VALUE MEASUREMENTS - Fair value on a recurring basis (Details) - USD ($) $ / shares in Units, $ in Millions |
Sep. 30, 2018 |
Mar. 31, 2018 |
|---|---|---|
| Other long-term assets: | ||
| Share Price | $ 5.19 | |
| Recurring basis | ||
| Other long-term assets: | ||
| Money market mutual funds | $ 0.5 | |
| Total assets at fair value | 11.3 | |
| Other long-term liabilities: | ||
| Derivative liability | 144.5 | |
| Total liabilities at fair value | 144.5 | |
| Recurring basis | Mutual Fund Fixed Income | ||
| Other long-term assets: | ||
| Equity securities, available-for-sale: | 10.8 | |
| Recurring basis | Quoted prices in active market (Level 1) | ||
| Other long-term assets: | ||
| Money market mutual funds | 0.5 | |
| Total assets at fair value | 0.5 | |
| Recurring basis | Significant unobservable inputs (Level 3) | ||
| Other long-term liabilities: | ||
| Derivative liability | 144.5 | |
| Total liabilities at fair value | $ 144.5 |