STOCK-BASED COMPENSATION - Stock option activity (Details)	6 Months Ended
	Jun. 30, 2020 $ / shares shares
Number of Shares
Beginning balance (in shares) | shares	10,834
Exercised (in shares) | shares	(10,834)
Weighted Average Exercise Price
Beginning balance (in dollars per share) | $ / shares	$ 18.59
Exercised (in dollars per share) | $ / shares	$ 18.59