STOCKHOLDERS' EQUITY - ADDITIONAL INFORMATION (Detail) - USD ($)	3 Months Ended	9 Months Ended
	Sep. 30, 2017	Sep. 30, 2017	Sep. 30, 2018	Dec. 31, 2017	Dec. 26, 2017	Oct. 22, 2014	Nov. 01, 2007
Class of Stock [Line Items]
Stock repurchase program, additional authorized amount						$ 30,000,000	$ 50,000,000
Repurchased shares (in shares)	48,687	48,687
Repurchased shares, value	$ 328,000	$ 328,000
Stock repurchase program, average cost per share (in dollars per share)	$ 6.73	$ 6.73
Stock repurchase program, remaining available repurchase amount			$ 33,400,000
Common stock, par value (in dollars per share)			$ 0.001	$ 0.001	$ 0.001
Rights, exercised (in shares)	0	0	0
Series B Junior Participating Preferred Stock
Class of Stock [Line Items]
Right, exercise price (in dollars per share)					$ 30.00