BUSINESS COMBINATIONS - Additional Information (Details) $ in Thousands			12 Months Ended
	Apr. 02, 2018 USD ($) facility	Jul. 06, 2017 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2017 USD ($)
Business Acquisition [Line Items]
Bargain purchase gain			$ 0	$ 0	$ 1,434
ABILITY Network
Business Acquisition [Line Items]
Consideration transferred	$ 1,191,050
Number of provider facilities | facility	44,000
Acquisition related costs				$ 6,500
Consideration paid in cash	$ 1,107,220
Cash and cash equivalents	$ 23,850
ComplexCare Solutions, Inc.
Business Acquisition [Line Items]
Consideration paid in cash		$ 4,500
Contingent consideration		2,300
Assets acquired		9,800
Cash and cash equivalents		1,500
Liabilities assumed		3,900
Bargain purchase gain		$ 1,400