Calculation of Weighted Average Common Shares and Common Equivalent Shares Outstanding (Details) (USD $) In Thousands, except Share data, unless otherwise specified	3 Months Ended
Dec. 31, 2014	Dec. 31, 2013
Earnings Per Share [Abstract]
Net income (loss)	$ (5,445)us-gaap_NetIncomeLoss	$ 24,176us-gaap_NetIncomeLoss
Less: Income (loss) allocable to unvested restricted stock	70	(152)
Income (loss) available to common shareholders	(5,375)	24,024
Reallocation of participating earnings		1
Income (loss) attributable to common shareholders for diluted earnings per share	$ (5,375)	$ 24,025
Weighted average number of common share equivalents:
Common shares used in basic earnings (loss) per share	12,977,913	12,947,195
Common share equivalents outstanding related to stock options		52,918
Total weighted average common shares and common share equivalents used in diluted earnings (loss) per share	12,977,913	13,000,113
Basic	$ (0.41)us-gaap_EarningsPerShareBasic	$ 1.86us-gaap_EarningsPerShareBasic
Diluted	$ (0.41)us-gaap_EarningsPerShareDiluted	$ 1.85us-gaap_EarningsPerShareDiluted

Reallocation of participating earnings.

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The amount of net income (loss) for the period per each share of common stock or unit outstanding during the reporting period.

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

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Net income after adjustments for dividends on preferred stock (declared in the period) and/or cumulative preferred stock (accumulated for the period).

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Net Income or Loss Available to Common Stockholders plus adjustments resulting from the assumption that dilutive convertible securities were converted, options or warrants were exercised, or that other shares were issued upon the satisfaction of certain conditions.

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Aggregate of earnings distributed and earnings allocated to participating securities under the two-class method to the extent that participating securities may share in earnings as if all of the earnings for the period had been distributed.

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The sum of dilutive potential common shares or units used in the calculation of the diluted per-share or per-unit computation.

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The average number of shares or units issued and outstanding that are used in calculating diluted EPS or earnings per unit (EPU), determined based on the timing of issuance of shares or units in the period.

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Number of [basic] shares or units, after adjustment for contingently issuable shares or units and other shares or units not deemed outstanding, determined by relating the portion of time within a reporting period that common shares or units have been outstanding to the total time in that period.

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