STOCK-BASED COMPENSATION - Non-Qualified Stock Option Award Activity (Details) - Stock Option Awards - USD ($)	3 Months Ended	12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017
Shares
Outstanding (in shares)	0
Outstanding (in shares)		0
Exercisable (in shares)		0
Amended and Restated 2010 Equity Incentive Plan
Shares
Outstanding (in shares)	90,000
Granted (in shares)	0
Exercised (in shares)	0
Outstanding (in shares)	90,000	90,000
Exercisable (in shares)	86,600	73,000
Weighted Average Exercise Price (in dollars per share)
Outstanding (in dollars per share)	$ 52.71
Outstanding (in dollars per share)	52.71	$ 52.71
Exercisable (in dollars per share)	$ 52.52	$ 51.94
Weighted Average Remaining Contractual Term
Outstanding	6 years 8 months 23 days
Exercisable	6 years 8 months 16 days	6 years 10 months 17 days
Stock-based compensation
Aggregate Intrinsic Value, Outstanding (in dollars)	$ 912,900
Aggregate Intrinsic Value, Exercisable (in dollars)	$ 894,846	$ 843,968