v3.8.0.1

SHARE-BASED COMPENSATION - RSU Activity - Summary of Change (Details) - USD ($) | 12 Months Ended
--- | ---
Dec. 31, 2017 | Dec. 31, 2016 | Dec. 31, 2015
Number of Restricted Stock Units [Roll Forward] |  |  |
RSUs beginning | 2,074,794 |  |
RSUs awarded | 808,443 | 1,123,000 | 796,000
RSUs assumed in Merger | 2,255,312 |  |
RSUs released | (474,069) | (611,000) | (406,000)
RSUs forfeited | (379,190) | (27,000) | (58,000)
RSUs ending | 4,285,290 | 2,074,794 |
Weighted Average Purchase Price RSUs | $ 0 |  |
Weighted Average Remaining Contractual Term (Years) RSUs | 1 year 2 months 12 days |  |
Aggregate Intrinsic Value RSUs | $ 23,870,025 |  |
Number of RSUs vested and expected to vest | 4,112,791 |  |
Weighted Average Purchase Price of RSUs vested and expected to vest | $ 0 |  |
Weighted Average Remaining Contractual Term (Years) of RUSs vested and expected to vest | 1 year 2 months 12 days |  |
Aggregate Intrinsic Value RSUs vested and expected to vest | $ 23,090,689 |  |
Number of RSUs exercisable | 48,880 |  |
Weighted Average Purchase Price of RUSs exercisable | $ 0 |  |
Weighted Average Remaining Contractual Term (Years) of RUSs exercisable | 0 years |  |
Aggregate Intrinsic Value RSUs exercisable | $ 537,680 |  |
Weighted average remaining recognition period in years | 2 years 1 month 6 days |  |
Unamortized compensation expense, net of estimated forfeitures | $ 26,899,098 |  |

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