Equity and Stock-Based Compensation (Stock Options Valuation) (Details) - $ / shares	12 Months Ended
Sep. 30, 2017	Sep. 30, 2016	Sep. 30, 2015
Options [Roll Forward]
Outstanding at end of period (in shares)	1,560,441
Stock Options
Share-based Compensation Arrangement by Share-based Payment Award [Line Items]
Risk free interest rate	2.00%	2.00%	2.00%
Expected life	6 years	6 years	6 years
Dividend rate	0.00%	0.00%	0.00%
Volatility	63.00%	63.00%	67.00%
Options [Roll Forward]
Outstanding at beginning of period (in shares)	1,841,567	1,627,477	1,063,324
Granted (in shares)	145,000	360,075	327,500
Assumed - merger (shares)	0	0	367,229
Exercised (in shares)	(317,986)	(15,346)	(94,701)
Forfeited/canceled (in shares)	(108,140)	(130,639)	(35,875)
Outstanding at end of period (in shares)	1,560,441	1,841,567	1,627,477
Weighted Average Exercise Price [Abstract]
Outstanding at beginning of period (usd per share)	$ 8.15	$ 9.11	$ 7.37
Granted (usd per share)	5.23	5.25	9.74
Assumed - merger (usd per share)		0.00	14.19
Exercised (usd per share)	6.30	3.28	5.52
Forfeited (usd per share)	12.71	12.86	24.71
Outstanding at end of period (usd per share)	$ 7.95	$ 8.15	$ 9.11
Exercisable at end of period (in shares)	1,055,865	1,127,611	1,002,421
Exercisable at end of period, weighted average exercise price (usd per share)	$ 8.58	$ 8.92	$ 9.74
Weighted average grant-date fair value of options granted during the period (usd per share)	$ 3.04	$ 3.03	$ 5.91

Share-based Compensation Arrangement by Share-based Payment Award, Options, Assumed In Merger

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- Definition

Share-based Compensation Arrangements by Share-based Payment Award, Options, Assumed In Merger, Weighted Average Exercise Price

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- Definition

The estimated dividend rate (a percentage of the share price) to be paid (expected dividends) to holders of the underlying shares over the option's term.

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The estimated measure of the percentage by which a share price is expected to fluctuate during a period. Volatility also may be defined as a probability-weighted measure of the dispersion of returns about the mean. The volatility of a share price is the standard deviation of the continuously compounded rates of return on the share over a specified period. That is the same as the standard deviation of the differences in the natural logarithms of the stock prices plus dividends, if any, over the period.

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The risk-free interest rate assumption that is used in valuing an option on its own shares.

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Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

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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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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 weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.

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

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- Definition

A roll forward is a reconciliation of a concept from the beginning of a period to the end of a period.

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

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

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- Definition

Expected term of share-based compensation awards, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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

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