Net Income Per Common Share - Additional Information (Detail) - shares shares in Millions |
3 Months Ended | |
|---|---|---|
Jan. 31, 2017 |
Jan. 31, 2016 |
|
| Earnings Per Share [Abstract] | ||
| Antidilutive Securities Excluded from Computation of Earnings Per Share, Amount | 8.0 | 3.4 |