Stock-based Compensation - Stock options and SSARs outstanding (Details) (SSARs / Stock Options, USD $)	3 Months Ended	6 Months Ended
Mar. 31, 2015	Mar. 31, 2015	Dec. 31, 2014	Sep. 30, 2014
SSARs / Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Shares outstanding at beginning of period (shares)	646,630	646,630	650,223	650,233
Options Granted	0	0
Share-Based Compensation Arrangement By ShareBased Payment Award, Exercises In Period	456	456
Share-based Compensation Arrangement by Share-based Payment Award, Expirations in Period	0	0
Share-based Compensation Arrangement by Share-based Payment Award, Forfeitures in Period	3,137	3,147
Exercisable at end of period (shares)	491,932	491,932
Vested or expected to vest in the future (shares)	646,437	646,437
Weighted average exercise price of shares outstanding at beginning of period (in US$ per share)	$ 18.12	$ 18.12	$ 18.12	$ 18.12
Share-based Compensation Arrangements by Share-based Payment Award, Grants in Period, Weighted Average Exercise Price	$ 0.00	$ 0.00
Share-based Compensation Arrangements by Share-based Payment Award, Exercises in Period, Weighted Average Exercise Price	$ 12.07	$ 12.07
Share-based Compensation Arrangements by Share-based Payment Award, Expirations in Period, Weighted Average Exercise Price	$ 0.00	$ 0.00
Share-based Compensation Arrangements by Share-based Payment Award, Forfeitures in Period, Weighted Average Exercise Price	$ 20.32	$ 20.32
Weighted average exercise price of shares exercisable at end of period (in US$ per share)	$ 18.39	$ 18.39
Weighted average exercise price of shares vested or expected to vest in the future (in US$ per share)	$ 18.12	$ 18.12

Share-based Compensation Arrangement by Share-based Payment Award, Expirations in Period

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Expirations in Period, Weighted Average Exercise Price

+ References

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- Definition

The number of grants made during the period on other than stock (or unit) option plans (for example, phantom stock or unit plan, stock or unit appreciation rights plan, performance target plan).

+ References

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-Publisher FASB

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- Definition

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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- Definition

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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- Definition

Number of options outstanding, including both vested and non-vested options.

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- Definition

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

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- Definition

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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- Definition

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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- Definition

Weighted average price at which option holders acquired shares when converting their stock options into shares.

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- Definition

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 per share amount at which grantees can acquire shares of common stock by exercise of options.

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Number of share options (or share units) exercised during the current period.

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-Number 210

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