REVENUE RECOGNITION - Summary of Changes in Revenue Contract Liability (Details)  | 
6 Months Ended | 
|---|---|
| 
 Jun. 30, 2018  
USD ($) 
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| Revenue From Contract With Customer [Abstract] | |
| Beginning balance – January 1, 2018 | $ 1,083,639 | 
| Increase (advanced billings) | 6,730,824 | 
| Decrease (revenue recognition) | (6,627,156) | 
| Ending balance – June 30. 2018 | $ 1,187,307 | 
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- Definition Contract with customer decrease in revenue recognition. No definition available. 
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- Definition Contract with customer increase in advanced billings. No definition available. 
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- Definition Amount of obligation to transfer good or service to customer for which consideration has been received or is receivable, classified as current. Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef 
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- References No definition available. 
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