STOCK-BASED COMPENSATION - ACTIVITY OF STOCK OPTIONS (Details) - LTIP $ / shares in Units, $ in Thousands	9 Months Ended
	Sep. 30, 2021 USD ($) $ / shares shares
Stock Options
Outstanding, beginning of year (in shares) | shares	72,368
Granted (in shares) | shares	0
Exercised (in shares) | shares	(21,878)
Forfeited (in shares) | shares	(510)
Outstanding, end of quarter (in shares) | shares	49,980
Number of options outstanding and exercisable (in shares) | shares	49,980
Weighted-Average Exercise Price
Outstanding, beginning of year (in dollars per share) | $ / shares	$ 34.36
Granted (in dollars per share) | $ / shares	0
Exercised (in dollars per share) | $ / shares	34.36
Forfeited (in dollars per share) | $ / shares	34.36
Outstanding, end of quarter (in dollars per share) | $ / shares	34.36
Number of options outstanding and exercisable (in dollars per share) | $ / shares	$ 34.36
Additional Information
Weighted-Average Remaining Contractual Term (in years)	5 years 7 months 6 days
Weighted-Average Remaining Contractual Term, Number of options outstanding and exercisable (in years)	5 years 7 months 6 days
Aggregate Intrinsic Value (in thousands) | $	$ 677
Aggregate Intrinsic Value, Number of options outstanding and exercisable (in thousands) | $	$ 677