Employee Benefits - Summary of Stock Option Plans (Detail) $ / shares in Units, shares in Thousands, $ in Thousands	12 Months Ended
Sep. 30, 2019 USD ($) $ / shares shares
Disclosure of Compensation Related Costs, Share-based Payments [Abstract]
Outstanding beginning of period, Options \| shares	1,095
Grants, Options \| shares	77
Exercises, Options \| shares	(30)
Forfeitures, Options \| shares	(52)
Cancellations, Options \| shares	(100)
Outstanding end of period, Options \| shares	990
Exercisable end of period, Options \| shares	782
Outstanding beginning of period, Weighted Average Exercise Price \| $ / shares	$ 17.56
Grants, Weighted Average Exercise Price \| $ / shares	16.07
Exercises, Weighted average exercise price \| $ / shares	15.13
Forfeitures, Weighted average exercise price \| $ / shares	15.03
Cancellations, Weighted average exercise price \| $ / shares	20.48
Outstanding end of period, Weighted Average Exercise Price \| $ / shares	17.36
Exercisable end of period, Weighted average exercise price \| $ / shares	$ 17.99
Outstanding end of period, Weighted Average remaining life	6 years 4 months 13 days
Exercisable end of period, Weighted Average remaining life	5 years 10 months 9 days
Outstanding end of period, Aggregate intrinsic value \| $	$ 1

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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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Number of options or other stock instruments for which the right to exercise has lapsed under the terms of the plan agreements.

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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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Amount by which the current fair value of the underlying stock exceeds the exercise price of options outstanding.

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

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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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Weighted average remaining contractual term for vested portions of options outstanding and currently exercisable or convertible, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.

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Weighted average remaining contractual term for option awards outstanding, 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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Share based compensation arrangements by share based payment award options cancellations in period weighted average exercise price.

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