DESCRIPTION OF BUSINESS AND ACCOUNTING POLICIES - Sales, Marketing and Operations Expense (Details) - USD ($) $ in Millions |
12 Months Ended | ||
|---|---|---|---|
Dec. 31, 2020 |
Dec. 31, 2019 |
Dec. 31, 2018 |
|
| DESCRIPTION OF BUSINESS AND ACCOUNTING POLICIES | |||
| Advertising costs | $ 33.1 | $ 75.2 | $ 38.9 |