Commitments and Contingencies	6 Months Ended
Apr. 30, 2017
Commitments and Contingencies Disclosure [Abstract]
Commitments and Contingencies	COMMITMENTS AND CONTINGENCIES Letters of Credit and Surety Bonds We use letters of credit and surety bonds to secure certain commitments related to insurance programs and for other purposes. As of April 30, 2017, these letters of credit and surety bonds totaled $128.9 million and $546.6 million, respectively. Guarantees In some instances, we offer clients guaranteed energy savings under certain energy savings contracts. At April 30, 2017 and October 31, 2016, total guarantees were $88.5 million and $60.9 million, respectively, and these guarantees extend through 2032 and 2031, respectively. We accrue for the estimated cost of guarantees when it is probable that a liability has been incurred and the amount can be reasonably estimated. Historically, we have not incurred any material losses in connection with these guarantees. In connection with an unconsolidated joint venture in which one of our subsidiaries has a 33% ownership interest, that subsidiary and the other joint venture partners have each jointly and severally guaranteed the obligations of the joint venture to perform under certain contracts extending through 2019. Annual revenues relating to the underlying contracts are approximately $35 million. Should the joint venture be unable to perform under these contracts, the joint venture partners would be jointly and severally liable for any losses incurred by the client due to the failure to perform. Sales Tax Audits We collect sales tax from clients and remit those collections to the applicable states. When clients fail to pay their invoices, including the amount of any sales tax that we advanced on their behalf, in some cases we are entitled to seek a refund of that amount of sales tax from the applicable state. Sales tax laws and regulations enacted by the various states are subject to interpretation, and our compliance with such laws is routinely subject to audit and review by such states. Audit risk is concentrated in several states, and these states are conducting ongoing audits. The outcomes of ongoing and any future audits and changes in the states’ interpretation of the sales tax laws and regulations could materially adversely impact our results of operations. Legal Matters We are a party to a number of lawsuits, claims, and proceedings incident to the operation of our business, including those pertaining to labor and employment, contracts, personal injury, and other matters, some of which allege substantial monetary damages. Some of these actions may be brought as class actions on behalf of a class or purported class of employees. At April 30, 2017, the total amount accrued for all probable litigation losses where a reasonable estimate of the loss could be made was $129.0 million. This $129.0 million includes the accrual of $115.0 million in connection with the probable settlements of the Augustus and Karapetyan cases discussed below, as well as an accrual for payroll taxes related to the probable settlements of $6.8 million. The remaining $7.2 million relates to various other probable litigation losses. Litigation outcomes are difficult to predict, and the estimation of probable losses requires the analysis of multiple possible outcomes that often depend on judgments about potential actions by third parties. There is the potential for a material adverse effect on our financial statements if one or more matters are resolved in a particular period in an amount materially in excess of what we anticipated. We do not accrue for contingent losses that, in our judgment, are considered to be reasonably possible but not probable. The estimation of reasonably possible losses also requires the analysis of multiple possible outcomes that often depend on judgments about potential actions by third parties. Our management currently estimates the range of loss for all reasonably possible losses for which a reasonable estimate of the loss can be made is between zero and $16 million. Factors underlying this estimated range of loss may change from time to time, and actual results may vary significantly from this estimate. In some cases, although a loss is probable or reasonably possible, we cannot reasonably estimate the maximum potential losses for probable matters or the range of losses for reasonably possible matters. Therefore, our accrual for probable losses and our estimated range of loss for reasonably possible losses do not represent our maximum possible exposure. While the results of these lawsuits, claims, and proceedings cannot be predicted with any certainty, our management believes that the final outcome of these matters will not have a material adverse effect on our financial position, results of operations, or cash flows. Certain Legal Proceedings Certain pending lawsuits to which we are a party are discussed below. In determining whether to include any particular lawsuit or other proceeding, we consider both quantitative and qualitative factors. These factors include, but are not limited to: the amount of damages and the nature of any other relief sought in the proceeding; if such damages and other relief are specified, our view of the merits of the claims; whether the action is or purports to be a class action, and our view of the likelihood that a class will be certified by the court; the jurisdiction in which the proceeding is pending; and the potential impact of the proceeding on our reputation. The Consolidated Cases of Augustus, Hall, and Davis, et al. v. American Commercial Security Services, filed July 12, 2005, in the Superior Court of California, Los Angeles County (the “Augustus case”) The Augustus case is a certified class action involving alleged violations of certain California state laws relating to rest breaks. The case centers on whether requiring security guards to remain on call during rest breaks violated Section 226.7 of the California Labor Code. On February 8, 2012, the plaintiffs filed a motion for summary judgment on the rest break claim, and on July 31, 2012, the Superior Court of California, Los Angeles County (the “Superior Court”), entered judgment in favor of plaintiffs in the amount of approximately $89.7 million (the “common fund”). Subsequently, the Superior Court also awarded plaintiffs’ attorneys’ fees of approximately $4.5 million in addition to approximately 30% of the common fund. Under California law, post-judgment interest on a judgment accrues at a rate of 10% simple interest per year from the date the judgment is entered until it is satisfied. We appealed the Superior Court’s rulings to the Court of Appeals of the State of California, Second Appellate District (the “Appeals Court”). On December 31, 2014, the Appeals Court issued its opinion, reversing the judgment in favor of the plaintiffs and vacating the award of $89.7 million in damages and the attorneys’ fees award. The plaintiffs filed a petition for review with the California Supreme Court on March 4, 2015, and on April 29, 2015, the California Supreme Court granted the plaintiffs’ petition. On December 22, 2016, the California Supreme Court rendered its decision, holding that on-call and on-duty rest breaks are prohibited by California law, and reversed the Appeals Court judgment on this issue. The amount of post-judgment interest as of December 22, 2016 was approximately $41.2 million. On February 6, 2017, ABM Security Services, Inc., a wholly-owned subsidiary of ABM Industries Incorporated, entered into a Class Action Settlement and Release with Plaintiffs Jennifer Augustus, Delores Hall, Emanuel Davis, and Carlton Anthony Waite, on behalf of themselves and the settlement class members, to settle the Augustus case on a class-wide basis for $110.0 million (the “Augustus Settlement Agreement”). On March 17, 2017, the Augustus Settlement Agreement was amended to address certain procedural matters. The Augustus Settlement Agreement, as amended, is contingent upon the approval of the Superior Court. On April 6, 2017, the Superior Court granted preliminary approval of the class action settlement. Notice to the class members was sent on April 24, 2017 and they have until June 8, 2017 to file any objections to the settlement. The Superior Court scheduled a final approval hearing for June 30, 2017. Karapetyan v. ABM Industries Incorporated and ABM Security Services, Inc., et al. filed on October 23, 2015, pending in the United States District Court for the Central District of California (the “Karapetyan case”) The Karapetyan case is a putative class action in which the plaintiff seeks to represent a class of security guards who worked during time periods subsequent to the class period in the Augustus case. The plaintiff alleges that ABM violated certain California state laws relating to meal and rest breaks and other wage and hour claims. On January 30, 2017, ABM entered into a Settlement Term Sheet with plaintiff to settle the case on a class-wide basis for $5.0 million. On April 17, 2017, ABM Industries Incorporated, ABM Security Services, Inc., ABM Onsite Services, Inc., and ABM Onsite Services – West, Inc. entered into a Class Action Settlement and Release with Plaintiff Vardan Karapetyan, on behalf of himself and the settlement class members, to settle the Karapetyan case (the “Karapetyan Settlement Agreement”) on a class-wide basis for $5.0 million. This settlement is contingent upon the final approval by the United States District Court for the Central District of California and the final approval by the Superior Court of the Augustus Settlement Agreement. The Consolidated Cases of Bucio and Martinez v. ABM Janitorial Services filed on April 7, 2006, in the Superior Court of California, County of San Francisco (the “Bucio case”) The Bucio case is a purported class action involving allegations that we failed to track work time and provide breaks. On April 19, 2011, the trial court held a hearing on plaintiffs’ motion to certify the class. At the conclusion of that hearing, the trial court denied plaintiffs’ motion to certify the class. On May 11, 2011, the plaintiffs filed a motion to reconsider, which was denied. The plaintiffs have appealed the class certification issues. The trial court stayed the underlying lawsuit pending the decision in the appeal. On August 30, 2012, the plaintiffs filed their appellate brief on the class certification issues. We filed our responsive brief on November 15, 2012. On January 18, 2017, the appeals court invited the parties to file supplemental letter briefs. ABM and plaintiffs each filed their respective supplemental letter briefs with the court on February 8, 2017. Oral argument relating to the appeal has not been scheduled. Hussein and Hirsi v. Air Serv Corporation filed on January 20, 2016, pending in the United States District Court for the Western District of Washington at Seattle (the “Hussein case”) The Hussein case is a certified class action involving a class of certain hourly Air Serv employees at Seattle-Tacoma International Airport in SeaTac, Washington. The plaintiffs allege that Air Serv violated a minimum wage requirement in an ordinance applicable to certain employers in the local city of SeaTac (“the Ordinance”). Plaintiffs seek retroactive wages, double damages, interest, and attorneys’ fees. This matter was removed to federal court. In a separate lawsuit brought by Filo Foods, LLC, Alaska Airlines, and several other employers at SeaTac airport, the King County Superior Court issued a decision that invalidated the Ordinance as it applied to workers at SeaTac airport. Subsequently, the Washington Supreme Court reversed the Superior Court’s decision. There are disputes in federal court concerning the legality of the Ordinance, its applicability to employers at SeaTac airport, and whether the plaintiffs are entitled to retroactive wages, double damages, interest, and attorneys’ fees. On February 7, 2017, a new lawsuit styled Abdirizak Isse et al. v. Air Serv Corporation (the “Isse case”), pending in the Superior Court of Washington for King County, was filed against Air Serv on behalf of sixty individual plaintiffs (who would otherwise be members of the Hussein class) who allege failure to comply with both the minimum wage provision and the sick and safe time provision of the Ordinance. The plaintiffs seek retroactive wages and sick benefits, double damages for wages and sick benefits, interest, and attorneys’ fees. The Isse case has since been expanded to ninety-two individual plaintiffs. In the event of a judgment against us in the Hussein case or the Isse case, we intend to seek reimbursement from our clients.

COMMITMENTS AND CONTINGENCIES

Letters of Credit and Surety Bonds

We use letters of credit and surety bonds to secure certain commitments related to insurance programs and for other purposes. As of April 30, 2017, these letters of credit and surety bonds totaled $128.9 million and $546.6 million, respectively.

Guarantees

In some instances, we offer clients guaranteed energy savings under certain energy savings contracts. At April 30, 2017 and October 31, 2016, total guarantees were $88.5 million and $60.9 million, respectively, and these guarantees extend through 2032 and 2031, respectively. We accrue for the estimated cost of guarantees when it is probable that a liability has been incurred and the amount can be reasonably estimated. Historically, we have not incurred any material losses in connection with these guarantees.

In connection with an unconsolidated joint venture in which one of our subsidiaries has a 33% ownership interest, that subsidiary and the other joint venture partners have each jointly and severally guaranteed the obligations of the joint venture to perform under certain contracts extending through 2019. Annual revenues relating to the underlying contracts are approximately $35 million. Should the joint venture be unable to perform under these contracts, the joint venture partners would be jointly and severally liable for any losses incurred by the client due to the failure to perform.

Sales Tax Audits

We collect sales tax from clients and remit those collections to the applicable states. When clients fail to pay their invoices, including the amount of any sales tax that we advanced on their behalf, in some cases we are entitled to seek a refund of that amount of sales tax from the applicable state. Sales tax laws and regulations enacted by the various states are subject to interpretation, and our compliance with such laws is routinely subject to audit and review by such states. Audit risk is concentrated in several states, and these states are conducting ongoing audits. The outcomes of ongoing and any future audits and changes in the states’ interpretation of the sales tax laws and regulations could materially adversely impact our results of operations.

Legal Matters

We are a party to a number of lawsuits, claims, and proceedings incident to the operation of our business, including those pertaining to labor and employment, contracts, personal injury, and other matters, some of which allege substantial monetary damages. Some of these actions may be brought as class actions on behalf of a class or purported class of employees.

At April 30, 2017, the total amount accrued for all probable litigation losses where a reasonable estimate of the loss could be made was $129.0 million. This $129.0 million includes the accrual of $115.0 million in connection with the probable settlements of the Augustus and Karapetyan cases discussed below, as well as an accrual for payroll taxes related to the probable settlements of $6.8 million. The remaining $7.2 million relates to various other probable litigation losses. Litigation outcomes are difficult to predict, and the estimation of probable losses requires the analysis of multiple possible outcomes that often depend on judgments about potential actions by third parties. There is the potential for a material adverse effect on our financial statements if one or more matters are resolved in a particular period in an amount materially in excess of what we anticipated.

We do not accrue for contingent losses that, in our judgment, are considered to be reasonably possible but not probable. The estimation of reasonably possible losses also requires the analysis of multiple possible outcomes that often depend on judgments about potential actions by third parties. Our management currently estimates the range of loss for all reasonably possible losses for which a reasonable estimate of the loss can be made is between zero and $16 million. Factors underlying this estimated range of loss may change from time to time, and actual results may vary significantly from this estimate.

In some cases, although a loss is probable or reasonably possible, we cannot reasonably estimate the maximum potential losses for probable matters or the range of losses for reasonably possible matters. Therefore, our accrual for probable losses and our estimated range of loss for reasonably possible losses do not represent our maximum possible exposure.

While the results of these lawsuits, claims, and proceedings cannot be predicted with any certainty, our management believes that the final outcome of these matters will not have a material adverse effect on our financial position, results of operations, or cash flows.

Certain Legal Proceedings

Certain pending lawsuits to which we are a party are discussed below. In determining whether to include any particular lawsuit or other proceeding, we consider both quantitative and qualitative factors. These factors include, but are not limited to: the amount of damages and the nature of any other relief sought in the proceeding; if such damages and other relief are specified, our view of the merits of the claims; whether the action is or purports to be a class action, and our view of the likelihood that a class will be certified by the court; the jurisdiction in which the proceeding is pending; and the potential impact of the proceeding on our reputation.

The Consolidated Cases of Augustus, Hall, and Davis, et al. v. American Commercial Security Services, filed July 12, 2005, in the Superior Court of California, Los Angeles County (the “Augustus case”)

The Augustus case is a certified class action involving alleged violations of certain California state laws relating to rest breaks. The case centers on whether requiring security guards to remain on call during rest breaks violated Section 226.7 of the California Labor Code. On February 8, 2012, the plaintiffs filed a motion for summary judgment on the rest break claim, and on July 31, 2012, the Superior Court of California, Los Angeles County (the “Superior Court”), entered judgment in favor of plaintiffs in the amount of approximately $89.7 million (the “common fund”). Subsequently, the Superior Court also awarded plaintiffs’ attorneys’ fees of approximately $4.5 million in addition to approximately 30% of the common fund. Under California law, post-judgment interest on a judgment accrues at a rate of 10% simple interest per year from the date the judgment is entered until it is satisfied. We appealed the Superior Court’s rulings to the Court of Appeals of the State of California, Second Appellate District (the “Appeals Court”). On December 31, 2014, the Appeals Court issued its opinion, reversing the judgment in favor of the plaintiffs and vacating the award of $89.7 million in damages and the attorneys’ fees award. The plaintiffs filed a petition for review with the California Supreme Court on March 4, 2015, and on April 29, 2015, the California Supreme Court granted the plaintiffs’ petition. On December 22, 2016, the California Supreme Court rendered its decision, holding that on-call and on-duty rest breaks are prohibited by California law, and reversed the Appeals Court judgment on this issue. The amount of post-judgment interest as of December 22, 2016 was approximately $41.2 million.

On February 6, 2017, ABM Security Services, Inc., a wholly-owned subsidiary of ABM Industries Incorporated, entered into a Class Action Settlement and Release with Plaintiffs Jennifer Augustus, Delores Hall, Emanuel Davis, and Carlton Anthony Waite, on behalf of themselves and the settlement class members, to settle the Augustus case on a class-wide basis for $110.0 million (the “Augustus Settlement Agreement”). On March 17, 2017, the Augustus Settlement Agreement was amended to address certain procedural matters. The Augustus Settlement Agreement, as amended, is contingent upon the approval of the Superior Court. On April 6, 2017, the Superior Court granted preliminary approval of the class action settlement. Notice to the class members was sent on April 24, 2017 and they have until June 8, 2017 to file any objections to the settlement. The Superior Court scheduled a final approval hearing for June 30, 2017.

Karapetyan v. ABM Industries Incorporated and ABM Security Services, Inc., et al. filed on October 23, 2015, pending in the United States District Court for the Central District of California (the “Karapetyan case”)

The Karapetyan case is a putative class action in which the plaintiff seeks to represent a class of security guards who worked during time periods subsequent to the class period in the Augustus case. The plaintiff alleges that ABM violated certain California state laws relating to meal and rest breaks and other wage and hour claims. On January 30, 2017, ABM entered into a Settlement Term Sheet with plaintiff to settle the case on a class-wide basis for $5.0 million. On April 17, 2017, ABM Industries Incorporated, ABM Security Services, Inc., ABM Onsite Services, Inc., and ABM Onsite Services – West, Inc. entered into a Class Action Settlement and Release with Plaintiff Vardan Karapetyan, on behalf of himself and the settlement class members, to settle the Karapetyan case (the “Karapetyan Settlement Agreement”) on a class-wide basis for $5.0 million. This settlement is contingent upon the final approval by the United States District Court for the Central District of California and the final approval by the Superior Court of the Augustus Settlement Agreement.

The Consolidated Cases of Bucio and Martinez v. ABM Janitorial Services filed on April 7, 2006, in the Superior Court of California, County of San Francisco (the “Bucio case”)

The Bucio case is a purported class action involving allegations that we failed to track work time and provide breaks. On April 19, 2011, the trial court held a hearing on plaintiffs’ motion to certify the class. At the conclusion of that hearing, the trial court denied plaintiffs’ motion to certify the class. On May 11, 2011, the plaintiffs filed a motion to reconsider, which was denied. The plaintiffs have appealed the class certification issues. The trial court stayed the underlying lawsuit pending the decision in the appeal. On August 30, 2012, the plaintiffs filed their appellate brief on the class certification issues. We filed our responsive brief on November 15, 2012. On January 18, 2017, the appeals court invited the parties to file supplemental letter briefs. ABM and plaintiffs each filed their respective supplemental letter briefs with the court on February 8, 2017. Oral argument relating to the appeal has not been scheduled.

Hussein and Hirsi v. Air Serv Corporation filed on January 20, 2016, pending in the United States District Court for the Western District of Washington at Seattle (the “Hussein case”)

The Hussein case is a certified class action involving a class of certain hourly Air Serv employees at Seattle-Tacoma International Airport in SeaTac, Washington. The plaintiffs allege that Air Serv violated a minimum wage requirement in an ordinance applicable to certain employers in the local city of SeaTac (“the Ordinance”). Plaintiffs seek retroactive wages, double damages, interest, and attorneys’ fees. This matter was removed to federal court. In a separate lawsuit brought by Filo Foods, LLC, Alaska Airlines, and several other employers at SeaTac airport, the King County Superior Court issued a decision that invalidated the Ordinance as it applied to workers at SeaTac airport. Subsequently, the Washington Supreme Court reversed the Superior Court’s decision. There are disputes in federal court concerning the legality of the Ordinance, its applicability to employers at SeaTac airport, and whether the plaintiffs are entitled to retroactive wages, double damages, interest, and attorneys’ fees. On February 7, 2017, a new lawsuit styled Abdirizak Isse et al. v. Air Serv Corporation (the “Isse case”), pending in the Superior Court of Washington for King County, was filed against Air Serv on behalf of sixty individual plaintiffs (who would otherwise be members of the Hussein class) who allege failure to comply with both the minimum wage provision and the sick and safe time provision of the Ordinance. The plaintiffs seek retroactive wages and sick benefits, double damages for wages and sick benefits, interest, and attorneys’ fees. The Isse case has since been expanded to ninety-two individual plaintiffs. In the event of a judgment against us in the Hussein case or the Isse case, we intend to seek reimbursement from our clients.