Condensed Consolidated Statements of Operations (Unaudited) - USD ($) shares in Thousands, $ in Thousands	3 Months Ended		9 Months Ended
	Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Income Statement [Abstract]
NET REVENUES	$ 51,737	$ 50,140	$ 160,471	$ 151,074
COST OF SALES	19,781	18,994	62,160	57,412
GROSS PROFIT	31,956	31,146	98,311	93,662
OPERATING EXPENSES
Research and development	4,259	3,964	13,245	11,512
Selling and marketing	8,504	7,961	25,962	23,645
General and administrative	8,377	8,289	26,155	23,302
Executive transition and realignment costs	913		5,105
Litigation costs	1,168		3,370
Goodwill impairment charge		6,628		6,628
Total operating expenses	23,221	26,842	73,837	65,087
OPERATING INCOME	8,735	4,304	24,474	28,575
OTHER INCOME (EXPENSE)
Interest income	109	51	271	102
Interest expense	(375)	(407)	(1,149)	(1,238)
Other, net	151	(2)	(94)	356
Total other income (expense)	(115)	(358)	(972)	(780)
EARNINGS BEFORE INCOME TAXES	8,620	3,946	23,502	27,795
INCOME TAX PROVISION	1,795	3,706	5,087	11,964
NET EARNINGS	$ 6,825	$ 240	$ 18,415	$ 15,831
BASIC EARNINGS PER COMMON SHARE	$ 0.16	$ 0.01	$ 0.44	$ 0.38
DILUTED EARNINGS PER COMMON SHARE	$ 0.16	$ 0.01	$ 0.43	$ 0.37
WEIGHTED AVERAGE NUMBER OF COMMON SHARES OUTSTANDING - BASIC	42,349	42,203	42,307	42,184
EFFECT OF DILUTIVE STOCK OPTIONS AND RESTRICTED SHARE UNITS	409	390	405	372
WEIGHTED AVERAGE NUMBER OF COMMON SHARES OUTSTANDING - DILUTED	42,758	42,593	42,712	42,556
ANTI-DILUTIVE SECURITIES:
Common share options and restricted share units	995	861	1,009	872
DIVIDENDS DECLARED PER COMMON SHARE	$ 0.125	$ 0.125	$ 0.375	$ 0.450