| **Share-Based Compensation - Additional Information (Detail) (USD $)**             | 3 Months Ended           |
|------------------------------------------------------------------------------------|--------------------------|
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| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Percentage of average closing price to be paid by employees                        | 85.00%                   |   |
| Share-based compensation                                                           | $ 374,000                | $ 326,000 |
| Estimated pre-vesting forfeiture rate                                              | 4.73%                    |   |
| Weighted-average grant date fair value for stock options                           | $ 5.32                   | $ 3.86 |
| Aggregate intrinsic value of stock options exercised                               | 18,000                   |   |
| Cash receipts of stock options exercised                                           | 16,000                   |   |
| Maximum                                                                            |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Common stock purchases through advance payroll deductions in a calendar year       | 25,000                   |   |
| Stock Options                                                                      |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Stock option term                                                                  | 10 years                 |   |
| Stock options vesting percentage                                                   | 100.00%                  |   |
| Unrecognized compensation expense                                                  | 94,000                   |   |
| Unrecognized compensation expense expected recognition period                      | 1 year 1 month 19 days   |   |
| Stock Options | Minimum                                                            |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Vested period                                                                      | 6 months                 |   |
| Stock Options | Maximum                                                            |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Vested period                                                                      | 2 years                  |   |
| Restricted Stock                                                                   |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Vested period                                                                      | 3 years                  |   |
| Unrecognized compensation expense                                                  | 3,071,000                |   |
| Unrecognized compensation expense expected recognition period                      | 1 year 10 months 10 days |   |
| Employee Stock Purchase Plan                                                       |                     |   |
| **Share-based Compensation Arrangement by Share-based Payment Award [Line Items]** |                     |   |
| Grant date fair value of ESPP options                                              | $ 17,000                 |   |

| X                                                                                                                                                                                                                                                                                                                                                         |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The maximum amount allowed for advance payroll deductions in a calendar year for employee stock purchase plan.
+ References
No definition available.
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| - Definition
Share Based Compensation Arrangement by Share Based Payment Award Contractual Term Range
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                   |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share based Compensation Arrangement by Share based Payment Award, Fair Value Assumptions, Annual Forfeiture Rate
+ References
No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                           |
|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation Arrangement By Share Based Payment Award Grant Date Fair Value Of Awards
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                |
|--------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation Arrangement by Share based Payment Award, Vesting Percentage
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No definition available.
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| X                                                                                                                                                                                                                                                                                                                                                                                                                                                                         |
|---------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Share Based Compensation Arrangements By Share Based Payment Award Percentage Of Market Price At Eligible Employees Granted Options To Purchase Shares
+ References
No definition available.
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| - Definition
Represents the expense recognized during the period arising from equity-based compensation arrangements (for example, shares of stock, unit, stock options or other equity instruments) with employees, directors and certain consultants qualifying for treatment as employees.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Weighted average period over which unrecognized compensation is expected to be recognized for equity-based compensation plans, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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| X                                                                                                                                                                                                                                                                                                                                                                                                                          |
|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Aggregate unrecognized cost of option awards made to employees under a stock option plan or plans, that have yet to vest.
+ References
No definition available.
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|-------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The cash inflow associated with the amount received from holders exercising their stock options. This item inherently excludes any excess tax benefit, which the entity may have realized and reported separately.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
Period which an employee's right to exercise an award is no longer contingent on satisfaction of either a service condition, market condition or a performance condition, in 'PnYnMnDTnHnMnS' format, for example, 'P1Y5M13D' represents the reported fact of one year, five months, and thirteen days.
+ References
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|----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The total accumulated difference between fair values of underlying shares on dates of exercise and exercise price on options which were exercised (or share units converted) into shares during the reporting period under the plan.
+ References
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|-----------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------------|
| - Definition
The weighted average grant-date fair value of options granted during the reporting period as calculated by applying the disclosed option pricing methodology.
+ References
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