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DEFERRED REVENUE (Details) - USD ($)
$ in Thousands
12 Months Ended
Dec. 31, 2019
Dec. 31, 2018
Dec. 31, 2017
Deferred Revenue Arrangement [Line Items]      
Deferred revenue $ 7,972 $ 8,658  
Amount recognized as revenue 263,492 $ 266,391 $ 282,756
Recognized over time for service [Member]      
Deferred Revenue Arrangement [Line Items]      
Amount recognized as revenue $ 6,785    
Minimum [Member]      
Deferred Revenue Arrangement [Line Items]      
Expected to be recognized over periods performance obligations 13 years    
Maximum [Member]      
Deferred Revenue Arrangement [Line Items]      
Expected to be recognized over periods performance obligations 15 years