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RELATED PARTY TRANSACTIONS (NARRATIVE) (Details) - USD ($)	3 Months Ended		9 Months Ended
	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Related Party Transaction Line Items
Sales Revenue Services Net	$ 395,507,000	$ 364,936,000	$ 1,182,378,000	$ 1,090,038,000
Airmax [Member]
Related Party Transaction Line Items
Purchases from Related Party			800,000	900,000
Accounts Payable Due from Related Party	$ 118,000		118,000
Convercent [Member]
Related Party Transaction Line Items
Purchases from Related Party			45,000	45,000
CafeX [Member]
Related Party Transaction Line Items
Purchases from Related Party			$ 50,000	44,000
Motif [Member]
Related Party Transaction Line Items
Lease Expiration Date			Mar. 31, 2019
Welltok
Related Party Transaction Line Items
Sales Revenue Services Net			$ 4,000,000	$ 3,400,000