LEASE COST (Details) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
	Sep. 30, 2019	Sep. 30, 2019
Lease Cost Table Line Items
Total lease cost	$ 14,086	$ 45,118
Depreciation and Amortization [Member]
Lease Cost Table Line Items
Amortization of ROU assets - finance leases	1,855	5,260
Interest Expense
Lease Cost Table Line Items
Interest on lease liabilities - finance leases	43	83
Cost of Services
Lease Cost Table Line Items
Operating lease cost (cost resulting from lease payments)	10,910	34,256
Short-term Lease, Cost	1,107	3,419
Selling General And Administrative Expenses [Member]
Lease Cost Table Line Items
Operating lease cost (cost resulting from lease payments)	551	3,181
Sublease Income	(126)	(319)
Other income (expense), net
Lease Cost Table Line Items
Operating lease cost (cost resulting from lease payments)	242	726
Sublease Income	$ (496)	$ (1,488)