NET INCOME PER SHARE (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended								12 Months Ended
	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2018	Mar. 31, 2017	Mar. 31, 2016
NET INCOME PER SHARE [Abstract]
Income from continuing operations	$ 10,020	$ 4,226	$ 6,601	$ 6,330	$ 7,543	$ 6,859	$ 11,487	$ 6,890	$ 27,177	$ 32,779	$ 31,074
Loss from discontinued operations, net of tax	0	0	0	0	7	(15)	(55)	0	0	(63)	(3)
Gain on sale of discontinued operations, net of tax									0	0	559
Net income	$ 10,020	$ 4,226	$ 6,601	$ 6,330	$ 7,550	$ 6,844	$ 11,432	$ 6,890	$ 27,177	$ 32,716	$ 31,630
Weighted average common shares outstanding [Abstract]
Basic (in shares)									22,672,000	22,515,000	22,661,000
Effect of dilutive securities [Abstract]
Restricted stock units (in shares)									463,000	282,000	221,000
Warrants (in shares)									0	0	1,000
Diluted (in shares)									23,135,000	22,797,000	22,883,000
Basic [Abstract]
Continuing operations (in dollars per share)	$ 0.44	$ 0.19	$ 0.29	$ 0.28	$ 0.33	$ 0.30	$ 0.51	$ 0.31	$ 1.20	$ 1.46	$ 1.37
Discontinued operations (in dollars per share)	0	0	0	0	0	0	0	0	0	(0.01)	0.03
Basic net income per share (in dollars per share)	0.44	0.19	0.29	0.28	0.33	0.30	0.51	0.31	1.20	1.45	1.40
Diluted [Abstract]
Continuing operations (in dollars per share)	0.43	0.18	0.29	0.28	0.33	0.30	0.51	0.30	1.17	1.44	1.36
Discontinued operations (in dollars per share)	0	0	0	0	0	0	(0.01)	0	0	0	0.02
Diluted net income per share (in dollars per share)	$ 0.43	$ 0.18	$ 0.29	$ 0.28	$ 0.33	$ 0.30	$ 0.50	$ 0.30	$ 1.17	$ 1.44	$ 1.38
Restricted Stock Units (RSUs) [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares underlying antidilutive restricted stock units (in shares)									0	2,000	92,000
Warrants [Member]
Antidilutive Securities Excluded from Computation of Earnings Per Share [Line Items]
Weighted average number of shares underlying antidilutive restricted stock units (in shares)									0	0	0