GOODWILL AND OTHER INTANGIBLE ASSETS - Placement Fee Agreements (Details) $ in Thousands	1 Months Ended	3 Months Ended		9 Months Ended
	Jul. 31, 2017 USD ($)	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) Agreement	Sep. 30, 2017 USD ($)	Sep. 30, 2016 USD ($) Agreement
Funding Agreements
Placement fees agreement amount	$ 49,100		$ 0
Unamortized fees related to superseded contract	$ 10,100
Cash payment made		$ 10,100		$ 13,132	$ 11,187
Number of placement fee agreements entered | Agreement			0		0
Contract rights under placement fee agreements
Funding Agreements
Payment advances made under placement fee agreements			$ 11,200		$ 11,200
Contract rights under placement fee agreements | Minimum
Funding Agreements
General term of the agreement				12 months
Contract rights under placement fee agreements | Maximum
Funding Agreements
General term of the agreement				83 months