GOODWILL (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |
|---|---|---|---|
Mar. 31, 2020 |
Mar. 31, 2019 |
Dec. 31, 2019 |
|
| Goodwill [Roll Forward] | |||
| Beginning balance | $ 317,676 | $ 293,525 | $ 293,525 |
| Goodwill acquired | 13,632 | 31,330 | |
| Goodwill related to partnership interest sold | 0 | (7,325) | |
| Goodwill write-off related to closed clinics | (1,859) | $ 0 | 0 |
| Goodwill adjustments for purchase price allocation of businesses acquired in prior year | 1,320 | 146 | |
| Ending balance | $ 330,769 | $ 317,676 | |