Face amount or stated value per share of common stock.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 210
-SubTopic 10
-Section S99
-Paragraph 1
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Unrecognized cost of unvested share-based compensation awards.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 718
-SubTopic 10
-Section 50
-Paragraph 2
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Cash received on stock transaction after deduction of issuance costs.

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The number of shares issued or sold by the subsidiary or equity method investee per stock transaction.

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Per share amount received by subsidiary or equity investee for each share of common stock issued or sold in the stock transaction.

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The aggregate amount of noncash, equity-based employee remuneration. This may include the value of stock or unit options, amortization of restricted stock or units, and adjustment for officers' compensation. As noncash, this element is an add back when calculating net cash generated by operating activities using the indirect method.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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Number of additional shares authorized for issuance under an established share-based compensation plan.

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The difference between the maximum number of shares (or other type of equity) authorized for issuance under the plan (including the effects of amendments and adjustments), and the sum of: 1) the number of shares (or other type of equity) already issued upon exercise of options or other equity-based awards under the plan; and 2) shares (or other type of equity) reserved for issuance on granting of outstanding awards, net of cancellations and forfeitures, if applicable.

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Period from grant date that an equity-based award expires, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Reference 1: http://www.xbrl.org/2003/role/presentationRef
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Gross number of shares (or other type of equity) issued during the period as a result of any equity-based compensation plan other than an employee stock ownership plan (ESOP). Shares issued could result from the issuance of restricted stock, the exercise of stock options, stock issued under employee stock purchase plans, and/or other employee benefit plans.

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Equity and Stock-Based Compensation (Details) - USD ($) $ / shares in Units, $ in Thousands			12 Months Ended				84 Months Ended	120 Months Ended
	Aug. 23, 2017	Aug. 18, 2017	Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015	Dec. 31, 1996	Dec. 31, 2015	Dec. 31, 2014	Apr. 30, 2007
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common stock, par value (in usd per share)		$ 0.01	$ 0.01	$ 0.01
Stock-based compensation expense			$ 1,328	$ 1,390	$ 1,162
Compensation cost not yet recognized			$ 900
Shares available to grant (in shares)			793,632
Option vesting period			1 year 1 month 18 days
2007 Employee Stock Incentive Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant (in shares)			686,032
2007 Employee Stock Incentive Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant (in shares)									500,000
Number of additional shares authorized (in shares)							2,500,000
1998 Employee Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant (in shares)			0
Non-Employee Directors Stock Option Plan
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares available to grant (in shares)			107,600
Non-Employee Directors Stock Option Plan \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of additional shares authorized (in shares)								400,000
Share-based compensation, shares issued (in shares)						100,000
Minimum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Option vesting period			6 months
Maximum \| Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Expiration period			10 years
Option vesting period			4 years
Offering
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)	1,213,250	1,055,000
Sale of stock price per share (in usd per share)	$ 9.50	$ 9.50
Proceeds from sale of stock	$ 10,600
Over-Allotment Option
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Number of shares sold (in shares)		158,250