XML 51 R33.htm IDEA: XBRL DOCUMENT
v3.20.2

Basis of Presentation and Significant Accounting Policies - Narrative (Details) | Jul. 31, 2020 USD ($) | Oct. 31, 2019 USD ($)
--- | --- | ---
Unusual or Infrequent Item, or Both [Line Items] |  |
Accrued compensation | $ 153,700,000 | $ 189,300,000
Pandemic |  |
Unusual or Infrequent Item, or Both [Line Items] |  |
Percent of health insurance premiums paid by employer | 1 |
Accrued compensation | $ 0 |

X
- Definition Compensation Related Costs, Percent of Health Insurance Premiums Paid by Employer, COVID-19 + References No definition available. + Details
Name: | abm_CompensationRelatedCostsPercentOfHealthInsurancePremiumsPaidByEmployerCOVID19
Namespace Prefix: | abm_
Data Type: | xbrli:pureItemType
Balance Type: | na
Period Type: | instant

X
- Definition Total of the carrying values as of the balance sheet date of obligations incurred through that date and payable for obligations related to services received from employees, such as accrued salaries and bonuses, payroll taxes and fringe benefits. Used to reflect the current portion of the liabilities (due within one year or within the normal operating cycle if longer). + References Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef -Publisher FASB -Name Accounting Standards Codification -Topic 210 -SubTopic 10 -Section S99 -Paragraph 1 -Subparagraph (SX 210.5-02.20) -URI http://asc.fasb.org/extlink&oid=6877327&loc=d3e13212-122682 + Details
Name: | us-gaap_EmployeeRelatedLiabilitiesCurrent
Namespace Prefix: | us-gaap_
Data Type: | xbrli:monetaryItemType
Balance Type: | credit
Period Type: | instant

X
- Definition Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table. + References No definition available. + Details
Name: | us-gaap_UnusualOrInfrequentItemLineItems
Namespace Prefix: | us-gaap_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Details
Name: | us-gaap_UnusualOrInfrequentItemAxis=abm_PandemicMember
Namespace Prefix: |
Data Type: | na
Balance Type: |
Period Type: |