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RELATED PARTY TRANSACTIONS (NARRATIVE) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Related Party Transaction Line Items
Sales Revenue Services Net	$ 392,515,000	$ 349,853,000	$ 786,871,000	$ 725,102,000
Airmax [Member]
Related Party Transaction Line Items
Purchases from Related Party			600,000	700,000
Accounts Payable Due from Related Party	$ 257,000		257,000
Convercent [Member]
Related Party Transaction Line Items
Purchases from Related Party			30,000	30,000
CafeX [Member]
Related Party Transaction Line Items
Purchases from Related Party			$ 33,000	29,000
Motif [Member]
Related Party Transaction Line Items
Lease Expiration Date			Mar. 31, 2019
Welltok
Related Party Transaction Line Items
Sales Revenue Services Net			$ 2,800,000	$ 2,000,000