STOCK-BASED COMPENSATION - Stock Option Activity (Details) - Stock options	12 Months Ended
	Dec. 31, 2019 USD ($) $ / shares shares
Shares
Stock Option Shares outstanding at beginning of period (in shares) | shares	2,236,864
Stock Option Shares granted (in shares) | shares	352,617
Stock Option Shares exercised (in shares) | shares	(222,362)
Stock Option Shares forfeited (in shares) | shares	(30,000)
Stock Option Shares outstanding at end of period (in shares) | shares	2,337,119
Stock Option Shares exercisable at end of period (in shares) | shares	1,107,468
Weighted-Average Exercise Price
Stock Option Shares outstanding at beginning of period (in dollars per share) | $ / shares	$ 26.21
Stock Option Shares granted (in dollars per share) | $ / shares	43.66
Stock Option Shares exercised (in dollars per share) | $ / shares	18.26
Stock Option Shares forfeited (in dollars per share) | $ / shares	34.77
Stock Option Shares outstanding at end of period (in dollars per share) | $ / shares	29.49
Stock Option Shares exercisable at end of period (in dollars per share) | $ / shares	$ 17.51
Weighted Average Remaining Contractual Term
Stock Option Shares outstanding at end of period	6 years 7 months 6 days
Stock Option Shares exercisable at end of period	4 years 8 months 12 days
Aggregate Intrinsic Value
Stock Option Shares outstanding at end of period (in dollars) | $	$ 43,371,603
Stock Option Shares exercisable at end of period (in dollars) | $	$ 34,371,603