Stock-Based Compensation - Additional Information (Detail) (USD $) | 6 Months Ended | 0 Months Ended | 3 Months Ended | 0 Months Ended | |
In Thousands, except Share data, unless otherwise specified | Apr. 30, 2015 | Apr. 30, 2014 | Jan. 20, 2015 | Apr. 30, 2015 | Feb. 06, 2015 | Apr. 30, 2011 |
| Directors |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Stock-based compensation expense | $719 | $303 | | | | |
2011 Management Incentive Plan [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Common stock shares authorized under ESPP | | | | | | 1,500,000 |
Stock-based compensation expense | 100 | | | 100 | | |
Number of non-employee directors | | | 12 | | | |
Weighted-average remaining life of stock options | 5 years 9 months 18 days | | | | | |
Exercisable stock options, weighted-average remaining contractual term | 4 years 2 months 12 days | | | | | |
2011 Management Incentive Plan [Member] | Non-employee directors [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Restricted stock closing price awarded | | | 40.39 | | | |
2011 Management Incentive Plan [Member] | Executive officers [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Restricted stock closing price awarded | | | | | $40.17 | |
2011 Management Incentive Plan [Member] | Stock Options [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Restricted shares issued per non-employee director | | | 1,750 | | | |
2011 Management Incentive Plan [Member] | Restricted Stock [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Total restricted shares issued to non-employee directors | | | 21,000 | | | |
2011 Management Incentive Plan [Member] | Restricted Stock [Member] | Non-employee directors [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Stock-based compensation expense | 300 | | | 300 | | |
2011 Management Incentive Plan [Member] | Restricted Stock [Member] | Executive officers [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Total restricted shares issued to executive officers | | | | | 55,394 | |
Shares vesting schedule | Shares vest in one-third increments, on an annual basis | | | | | |
Shares vesting schedule beginning date | 8-Jan-16 | | | | | |
Stock-based compensation expense | $200 | | | $200 | | |
2005 Stock Incentive Plan [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Weighted-average remaining life of stock options | 3 years 6 months | | | | | |
Exercisable stock options, weighted-average remaining contractual term | 3 years 1 month 6 days | | | | | |
2005 Stock Incentive Plan [Member] | Board of Director Members for October Two Thousand Eleven Option Grants [Member] | Maximum [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Term of vested stock options | 5 years | | | | | |
2005 Stock Incentive Plan [Member] | Board of Director Members for April Two Thousand Eleven Option Grants [Member] | Minimum [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Term of vested stock options | 2 years | | | | | |
2005 Stock Incentive Plan [Member] | Stock Options [Member] | Board of Director Members for October Two Thousand Eleven Option Grants [Member] | Maximum [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Stock options vesting period | 5 years | | | | | |
2005 Stock Incentive Plan [Member] | Stock Options [Member] | Board of Director Members for April Two Thousand Eleven Option Grants [Member] | Minimum [Member] | | | | | | |
Share-based Compensation Arrangement by Share-based Payment Award [Line Items] | | | | | | |
Stock options vesting period | 1 year | | | | | |