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Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.

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The maximum number of common shares permitted to be issued by an entity's charter and bylaws.

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Number of shares of common stock outstanding. Common stock represent the ownership interest in a corporation.

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Unrecognized cost of unvested share-based compensation awards.

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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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No definition available.

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The number of equity-based payment instruments, excluding stock (or unit) options, that were forfeited during the reporting period.

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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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No definition available.

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Number of share instruments newly issued under a share-based compensation plan.

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For net-share settlement of share-based awards when the employer settles employees' income tax withholding obligations, this element represents the number of shares the employees use to repay the employer.

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No definition available.

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

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The number of shares authorized to be repurchased by an entity's Board of Directors under a stock repurchase plan.

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No definition available.

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Total cost of shares repurchased divided by the total number of shares repurchased.

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Number of shares that have been repurchased during the period and are being held in treasury.

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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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Stockholders' Equity (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended		6 Months Ended
	Mar. 31, 2019	Mar. 31, 2018	Mar. 31, 2019	Mar. 31, 2018	May 02, 2019	Sep. 30, 2018
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	100,000,000		100,000,000			100,000,000
Common Stock, Shares, Outstanding	21,381,847		21,381,847			21,205,536
Options exercised				$ 11
Equity Class Of Treasury Stock [Line Items]
Approved Number of shares to be repurchased					1,000,000
Treasury Stock Value Acquired Cost Method	$ 3,200	$ 1,229	$ 5,411	$ 1,230
The 2006 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common Stock, Shares Authorized	3,000,000		3,000,000
Available Common Stock Authorized Shares	847,891		847,891
The 2015 Stock Repurchase Program [Member]
Equity Class Of Treasury Stock [Line Items]
Approved Number of shares to be repurchased	1,500,000		1,500,000
Treasury Stock Shares Acquired	189,821	79,817	235,954	79,817
Average Share Price	$ 16.7	$ 15.4	$ 16.58	$ 15.4
Restricted Stock [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under share based compensation program	283,195
Recognized compensation expense	$ 111	$ 131	$ 111	$ 245
Restricted Stock [Member] \| The 2006 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under share based compensation program			283,195
Unamortized compensation cost	3,685		$ 3,685
Phantom Share Units PSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares repurchased for tax withholding			87,609
Unvested shares forfeited			59,924
Shares issued under share based compensation program			212,688
Recognized compensation expense	$ 50	49	$ 99	91
Phantom Share Units PSUs [Member] \| Director [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under share based compensation program			3,991
Performance Based Phantom Share Units PPSUs [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares issued under share based compensation program	230,274
Recognized compensation expense	$ 465	$ (652)	$ 465	$ (449)
Unrestricted Stock [Member] \| The 2006 Equity Incentive Plan [Member]
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Common shares repurchased for tax withholding				520
Shares issued under share based compensation program				1,500