Equity (Schedule of Earnings per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2017	Jun. 30, 2017	Mar. 31, 2017	Dec. 31, 2016	Sep. 30, 2016	Jun. 30, 2016	Mar. 31, 2016	Dec. 31, 2015	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Numerator:
Income from continuing operations	$ 2,164	$ 2,436	$ 1,855	$ 1,766	$ 1,737	$ 1,178	$ (162)	$ (134)	$ 8,221	$ 2,619	$ (2,272)
(Loss) income from discontinued operations	41	(11)	(7)	(9)	259	123	4,144	1,121	14	5,647	65,372
Undistributed earnings allocated to common shareholders for basic and diluted net income per share	$ 2,205	$ 2,425	$ 1,848	$ 1,757	$ 1,996	$ 1,301	$ 3,982	$ 987	$ 8,235	$ 8,266	$ 63,100
Denominator:
Denominator for basic net income per share - weighted average shares outstanding (in shares)	26,904	26,833	26,622	26,279	26,177	26,103	25,942	25,697	26,659	25,979	30,012
Dilutive options outstanding, unvested stock units and ESPP (in shares)									885	539	0
Denominator for diluted net income per share - adjusted weighted average shares outstanding (in shares)	27,768	27,816	27,585	27,039	26,674	26,269	25,942	25,697	27,544	26,518	30,012
Net income (loss) per basic share:
Continuing operations (in usd per share)	$ 0.08	$ 0.09	$ 0.07	$ 0.07	$ 0.07	$ 0.05	$ (0.01)	$ 0.00	$ 0.31	$ 0.10	$ (0.08)
Discontinued operations (in usd per share)									0.00	0.22	2.18
Net income per basic share (in usd per share)									0.31	0.32	2.10
Net income (loss) per diluted share:
Continuing operations (in usd per share)	0.08	0.09	0.07	0.07	0.06	0.05	(0.01)	0.00	0.30	0.10	(0.08)
Discontinued operations (in usd per share)									0.00	0.21	2.18
Net income per diluted share (in usd per share)	$ 0.08	$ 0.09	$ 0.07	$ 0.07	$ 0.07	$ 0.05	$ 0.15	$ 0.04	$ 0.30	$ 0.31	$ 2.10
Weighted average antidilutive options, unvested restricted stock units and awards, warrants and ESPP shares excluded from the computation (in shares)									398	508	1,391
Average market price of common stock (in dollars per share)									$ 8.92	$ 5.88	$ 5.81

Average Market Price of Common Stock During the Period

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- Definition

Securities (including those issuable pursuant to contingent stock agreements) that could potentially dilute basic earnings per share (EPS) or earnings per unit (EPU) in the future that were not included in the computation of diluted EPS or EPU because to do so would increase EPS or EPU amounts or decrease loss per share or unit amounts for the period presented.