INCOME TAXES - Narrative (Details) SFr in Millions, $ in Millions	3 Months Ended			9 Months Ended
	Sep. 30, 2020 USD ($)	Sep. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2020 USD ($)	Sep. 30, 2019 CHF (SFr)	Sep. 30, 2019 USD ($)
Income Tax Contingency [Line Items]
Effective income tax rate	22.10%	(0.40%)		24.60%	(3.50%)	(3.50%)
Effective income tax rate reconciliation, tax expense, sale of Extremity Orthopedic business	$ 4.2			$ 4.2
Rebound
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, in-process research and development (IPR&D) expense		$ 59.9				$ 59.9
Foreign Tax Authority | Ministry of the Economy, Finance and Industry, France
Income Tax Contingency [Line Items]
Effective income tax rate reconciliation, tax benefit, reversal of valuation allowance	$ 3.2
Foreign Tax Authority | Swiss Federal Tax Administration (FTA)
Income Tax Contingency [Line Items]
Federal tax credit			$ 10.8
Effective income tax rate reconciliation, tax benefit, federal tax holiday | SFr					SFr 12