STOCK-BASED COMPENSATION Stock Option Activity (Detail)	3 Months Ended
	Mar. 31, 2018 $ / shares shares
Number of Shares
Options outstanding at beginning of period (in shares) | shares	879,810
Granted (in shares) | shares	0
Exercised (in shares) | shares	(5,500)
Cancelled (in shares) | shares	(32,199)
Options outstanding at end of period (in shares) | shares	842,111
Option Exercise Price
Granted, lower limit (in dollars per share)	$ 0
Granted, upper limit (in dollars per share)	0
Exercised, lower limit (in dollars per share)	5.0
Exercised, upper limit (in dollars per share)	6.9
Cancelled, lower limit (in dollars per share)	5.5
Cancelled, upper limit (in dollars per share)	17.11
Weighted Average Exercise Price
Granted (in dollars per share)	0.00
Exercised (in dollars per share)	5.75
Cancelled (in dollars per share)	$ 10.18