EMPLOYEE BENEFIT PLANS - Restricted Stock (Details) - $ / shares	12 Months Ended
	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Units
Granted (in shares)	109,220
Restricted Stock Units (RSUs)
Units
Non vested balance at beginning of period (in shares)	116,855	329,205	368,492
Granted (in shares)	38,700	45,993	42,136
Forfeited (in shares)	(5,278)	(22,934)	(1,080)
Vested (in shares)	(31,422)	(235,409)	(80,343)
Non vested balance at end of period (in shares)	118,855	116,855	329,205
Weighted Average  Grant-Date Fair Value
Non vested balance at beginning of period (in dollars per share)	$ 65.73	$ 25.42	$ 17.20
Granted (in dollars per share)	31.93	77.78	78.37
Forfeited (in dollars per share)	63.17	57.27	28.30
Vested (in dollars per share)	44.06	12.54	15.42
Non vested balance at end of period (in dollars per share)	$ 60.56	$ 65.73	$ 25.42