Share-Based Compensation: (Details) (USD $)	12 Months Ended
Sep. 30, 2012 item	Sep. 30, 2011	Sep. 30, 2010
Share-based compensation
Share-based compensation expense	$ 645,000	$ 371,000	$ 371,000
Excess (shortfall) in income tax benefits related to share-based compensation arrangements	(5,000)	7,000	(2,000)
Number of share-based compensation plans maintained by the company	3
1998 Plan
Share-based compensation
Share-based compensation expense	67,000	117,000	159,000
Number of shares of common stock reserved for awards	3,389,000
1998 Plan \| Stock options
Options
Outstanding at the beginning of the period (in shares)	387,800	491,200	606,549
Cancelled (in shares)	(11,600)	(103,400)	(115,349)
Outstanding at the end of the period (in shares)	376,200	387,800	491,200
Vested and expected to vest (in shares)	375,200
Options exercisable at the end of the period (in shares)	366,200
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 8.74	$ 9.21	$ 9.45
Cancelled (in dollars per share)	$ 12.65	$ 10.95	$ 10.49
Outstanding at the end of the period (in dollars per share)	$ 8.62	$ 8.74	$ 9.21
Vested and expected to vest (in dollars per share)	$ 8.60
Options exercisable at the end of the period (in dollars per share)	$ 8.64
2009 Plan
Share-based compensation
Share-based compensation expense	$ 377,000	$ 54,000	$ 23,000
Number of shares of common stock reserved for awards	1,200,000
Number of shares of common stock available for awards under the plan	655,333
2009 Plan \| Stock options
Options
Outstanding at the beginning of the period (in shares)	230,000	50,000
Granted (in shares)	280,000	180,000
Cancelled (in shares)	(50,000)
Outstanding at the end of the period (in shares)	460,000	230,000
Vested and expected to vest (in shares)	460,000
Options exercisable at the end of the period (in shares)	60,003
Weighted Average Exercise Price
Outstanding at the beginning of the period (in dollars per share)	$ 5.11	$ 4.50
Granted (in dollars per share)	$ 3.92	$ 5.28
Cancelled (in dollars per share)	$ 4.50
Outstanding at the end of the period (in dollars per share)	$ 4.45	$ 5.11
Vested and expected to vest (in dollars per share)	$ 4.45
Options exercisable at the end of the period (in dollars per share)	$ 5.28
2009 Plan \| Performance-based Award \| Employees
Share-based compensation
Maximum award (in shares)	300,000

The maximum award that a participant can receive, in shares, under the terms of a share based compensation plan.

No definition available.

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Represents the number of plans of share-based compensation arrangements maintained by the entity.

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No definition available.

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Adjustment to additional paid in capital related to the net effect of excess tax benefits and tax deficiencies associated with an equity-based compensation plan other than an employee stock ownership plan (ESOP).

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- Definition

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 shares (or other type of equity) originally approved (usually by shareholders and board of directors), net of any subsequent amendments and adjustments, for awards under the equity-based compensation plan. As stock or unit options and equity instruments other than options are awarded to participants, the shares or units remain authorized and become reserved for issuance under outstanding awards (not necessarily vested).

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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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The number of shares into which fully or partially vested stock options outstanding as of the balance sheet date can be currently converted under the option plan.

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The weighted-average price as of the balance sheet date at which grantees can acquire the shares reserved for issuance on vested portions of options outstanding and currently exercisable under the stock option plan.

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- Definition

The number of shares under options that were cancelled during the reporting period as a result of occurrence of a terminating event specified in contractual agreements pertaining to the stock option plan.

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Gross number of share options (or share units) granted during the period.

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The number of shares reserved for issuance under stock option agreements awarded under the plan that validly exist and are outstanding as of the balance sheet date, including vested options.

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Weighted average price at which grantees can acquire the shares reserved for issuance under the stock option plan.

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As of the balance sheet date, the number of shares into which fully vested and expected to vest stock options outstanding can be converted under the option plan.

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As of the balance sheet date, the weighted-average exercise price for outstanding stock options that are fully vested or expected to vest.

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Weighted average price at which grantees could have acquired the underlying shares with respect to stock options that were terminated.

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Weighted average price at which grantees can acquire the shares reserved for issuance on stock options awarded.

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