Earnings per Share - EPS Reconciliation (Details) (USD $) In Millions, except Share data, unless otherwise specified	3 Months Ended
Dec. 31, 2013	Dec. 31, 2012
Earnings Per Share [Abstract]
Net income	$ 2.5	$ 13.3
Less: Allocation to participating securities	(0.1)	(0.5)
Income from continuing operations allocated to common stockholders	2.4	12.8
Diluted net income	2.5	13.3
Less: Allocation to participating securities	(0.1)	(0.5)
Diluted net income allocated to common stockholders	$ 2.4	$ 12.8
Weighted average number of common shares outstanding	18,657,678	18,266,338
Weighted average number of dilutive potential common shares outstanding - Share-based awards	700,764	512,337
Weighted average number of diluted shares	19,358,442	18,778,675

Diluted net income allocated to common stockholders (diluted net income less allocation to participating securities).

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Income from continuing operations allocated to common stockholders (income from continuing operations attributable stockholders less allocation to participating securities plus interest on convertible debt less the allocation of the earnings from the interest on convertible debt to participating securities).

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Represents stock options and warrants included in the calculation of diluted earnings per share.

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Earnings from continuing operations allocated (not distributed) 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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Amount of income (loss) from continuing operations attributable to the parent. Also defined as revenue less expenses and taxes from ongoing operations before extraordinary items but after deduction of those portions of income or loss from continuing operations that are allocable to noncontrolling interests.

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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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Earnings allocated (not distributed) 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 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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