Equity (Schedule of Earnings per Share) (Details) - USD ($) $ / shares in Units, shares in Thousands, $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2019	Jun. 30, 2019	Mar. 31, 2019	Dec. 31, 2018	Sep. 30, 2018	Jun. 30, 2018	Mar. 31, 2018	Dec. 31, 2017	Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2017
Numerator:
(Loss) income from continuing operations	$ (14,975)	$ (10,477)	$ (4,994)	$ (5,538)					$ (35,984)	$ (17,453)	$ 8,221
Net loss					$ (5,886)	$ (8,414)	$ (3,071)	$ (82)	$ (35,984)	$ (17,453)	$ 8,235
Weighted-average number of basic and diluted shares outstanding (in shares)	28,734	28,005	27,652	27,534	27,424	27,387	27,197	27,032	27,983	27,266	26,659
Dilutive options outstanding, unvested stock units, unvested stock awards and ESPP									0	0	885
Denominator for diluted net (loss) income per share - adjusted weighted average shares outstanding									27,983	27,266	27,544
Net (loss) income per basic and fully diluted share (in usd per share)	$ (0.52)	$ (0.37)	$ (0.18)	$ (0.20)	$ (0.21)	$ (0.31)	$ (0.11)	$ 0.00	$ (1.29)	$ (0.64)	$ 0.31
Weighted average antidilutive options, unvested restricted stock units and awards, unvested performance stock units and ESPP shares excluded from the computation (in shares)									810	949	398
Average market price of common stock (in dollars per share)									$ 3.91	$ 5.87	$ 8.92

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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.

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The amount of net income or loss for the period per each share in instances when basic and diluted earnings per share are the same amount and reported as a single line item on the face of the financial statements. Basic earnings per share is the amount of net income or loss for the period per each share of common stock or unit outstanding during the reporting period. Diluted earnings per share includes the amount of net income or loss for the period available to each share of common stock or common unit outstanding during the reporting period and to each share or unit that would have been outstanding assuming the issuance of common shares or units for all dilutive potential common shares or units outstanding during the reporting period.

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Amount after tax of income (loss) from continuing operations including portion attributable to the noncontrolling interest.

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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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