Earnings per Share - EPS Reconciliation (Details) - USD ($) $ in Millions	3 Months Ended
Dec. 31, 2015	Dec. 31, 2014
Earnings Per Share [Abstract]
Net income	$ 8.8	$ 9.4
Less: Net income allocated to participating securities	(0.1)	(0.2)
Net income allocated to common shareholders	8.7	9.2
Diluted net income	8.8	9.4
Less: Diluted net income allocation to participating securities	(0.1)	(0.2)
Diluted net income allocated to common shareholders	$ 8.7	$ 9.2
Weighted average number of common shares outstanding	18,648,150	18,515,528
Dilutive potential common shares outstanding:
Incremental Common Shares Attributable to Dilutive Effect of Share-based Payment Arrangements	343,753	246,501
Diluted weighted-average shares	18,991,903	18,762,029

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

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Income from continuing operations allocated to common shareholders represents income from continuing operations attributable to shareholders 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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Undistributed Earnings Allocated to Participating Securities - Continuing Operations represents 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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Additional shares included in the calculation of diluted EPS as a result of the potentially dilutive effect of share based payment arrangements using the treasury stock method.

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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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Amount of undistributed earnings (loss) allocated to participating securities for the diluted earnings (loss) per share or per unit calculation under the two-class method.

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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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