BUSINESS SEGMENT - Schedule of Revenue by Category (Details) - USD ($) $ in Thousands |
3 Months Ended | 12 Months Ended | |||||||||
|---|---|---|---|---|---|---|---|---|---|---|---|
Dec. 31, 2017 |
Sep. 30, 2017 |
Jun. 30, 2017 |
Mar. 31, 2017 |
Dec. 31, 2016 |
Sep. 30, 2016 |
Jun. 30, 2016 |
Mar. 31, 2016 |
Dec. 31, 2017 |
Dec. 31, 2016 |
Dec. 31, 2015 |
|
| Segment Reporting Information [Line Items] | |||||||||||
| Revenues | $ 11,681 | $ 12,375 | $ 11,802 | $ 9,762 | $ 9,418 | $ 10,135 | $ 9,674 | $ 8,071 | $ 45,620 | $ 37,298 | $ 31,004 |
| Trauma and deformity | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Revenues | 32,801 | 26,844 | 22,475 | ||||||||
| Scoliosis | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Revenues | 11,585 | 9,349 | 7,446 | ||||||||
| Sports medicine/other | |||||||||||
| Segment Reporting Information [Line Items] | |||||||||||
| Revenues | $ 1,234 | $ 1,105 | $ 1,083 | ||||||||