| Component: (Network and Table) | |
|---|---|
| Network | 184 - Disclosure - RSU Activity (Detail) (http://www.abm.com/taxonomy/role/DisclosureRSUActivity) |
| Table | Reconciliation of Restricted Stock Activity [Table] |
| Reporting Entity [Axis] | 0000771497 (http://www.sec.gov/CIK) |
| Legal Entity [Axis] | Entity [Domain] |
| Statement Equity Components [Axis] | Restricted Stock Units R S U [Member] |
| Reconciliation of Restricted Stock Activity [Line Items] | Period [Axis] |
|---|---|
2011-11-01 - 2012-10-31 | |
Number of Shares | |
Outstanding at beginning of the year | 1,107,000 |
Granted | 430,000 |
Issued (including 36 shares withheld for income taxes) | (224,000) |
Forfeited | (82,000) |
Outstanding at end of period | 1,231,000 |
Vested at end of period | 224,000 |
Weighted-Average Grant Date Fair Value per Share | |
Outstanding at beginning of the year | 20.38 |
Granted | 18.77 |
Issued (including 63 shares withheld for income taxes) | 20.68 |
Forfeited | 20.55 |
Outstanding at end of period | 19.74 |
Vested at end of period | 20.68 |