Stockholders' Equity - Changes in Equity (Details) - USD ($) $ in Thousands	3 Months Ended	12 Months Ended
Sep. 30, 2018	Sep. 30, 2017	Jun. 30, 2018
Increase (Decrease) in Stockholders' Equity [Roll Forward]
Balance, beginning of period	$ 3,992
Stock based compensation	36
Share repurchases	(1)
Exercise of stock options	7
Net change on available-for-sale investments	31
Net loss	(2,238)	$ (3,006)	$ (13,300)
Balance, end of period	$ 1,827		$ 3,992

Amount of increase to additional paid-in capital (APIC) from recognition of equity-based compensation.

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A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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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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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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Value of stock issued as a result of the exercise of stock options.

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Total of all stockholders' equity (deficit) items, net of receivables from officers, directors, owners, and affiliates of the entity which are attributable to the parent. The amount of the economic entity's stockholders' equity attributable to the parent excludes the amount of stockholders' equity which is allocable to that ownership interest in subsidiary equity which is not attributable to the parent (noncontrolling interest, minority interest). This excludes temporary equity and is sometimes called permanent equity.

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Equity impact of the cost of common and preferred stock that were repurchased during the period. Recorded using the cost method.

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