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RELATED PARTY TRANSACTIONS (NARRATIVE) (Details) - USD ($)	3 Months Ended		6 Months Ended
	Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Related Party Transaction Line Items
Sales Revenue Services Net	$ 453,081,000	$ 392,515,000	$ 885,294,000	$ 786,871,000
Airmax [Member]
Related Party Transaction Line Items
Purchases from Related Party			200,000	600,000
Accounts Payable Due from Related Party	$ 50,000		50,000
CafeX [Member]
Related Party Transaction Line Items
Purchases from Related Party			0	33,000
Welltok
Related Party Transaction Line Items
Sales Revenue Services Net			$ 1,800,000	$ 2,800,000