Legal Matters	3 Months Ended
Sep. 30, 2011
Commitments and Contingencies Disclosure [Abstract]
Legal Matters	Legal Matters The Company and its subsidiaries are subject to claims and lawsuits typical of those filed against engineering and consulting companies. The Company carries liability insurance, including professional liability insurance, against such claims subject to certain deductibles and policy limits. Except as described herein, management is of the opinion that the resolution of these claims and lawsuits will not likely have a material effect on the Company's operating results, financial position and cash flows. The Arena Group v. TRC Environmental Corporation and TRC Companies, Inc., District Court Harris County, Texas, 2007. A former landlord of a subsidiary of the Company sued for damages alleging breach of a lease for certain office space in Houston, Texas which the subsidiary vacated. A jury verdict was rendered against the Company and its subsidiary on June 20, 2011. As a result, the Company took a charge in the fourth quarter of its fiscal year ended June 30, 2011 of $17,278 which included the full value of the verdict as well as pre-judgment interest. Subsequently, the Company filed a post-trial motion to disregard the late fee portion of the verdict, which was granted on October 5, 2011. As a result, the previously established reserve was reduced by $11,224. A judgment was entered in the case on October 10, 2011 and the Company is evaluating post-judgment and appellate measures. Interest accrues at 8% per annum on the amount ultimately determined to be payable until paid. Resolution of this matter may have a significant impact on the Company's cash flows, however the Company believes that existing cash resources, cash forecasted to be generated from operations and availability under its credit facility are adequate to meet this obligation. In re: World Trade Center Lower Manhattan Disaster Site Litigation, United States District Court for the Southern District of New York, 2006. A subsidiary of the Company has been named as a defendant (along with a number of other defendants) in a number of cases which are pending in the United States District Court for the Southern District of New York and are styled under the caption "In Re World Trade Center Lower Manhattan Disaster Site Litigation." The Complaints allege that the plaintiffs were workers involved in construction, demolition, excavation, debris removal and clean-up in the buildings surrounding the World Trade Center site, allege that plaintiffs were injured and seek unspecified damages for those injuries. The Company believes the subsidiary has meritorious defenses and is adequately insured, however an adverse determination in this matter could have a material effect on the Company's business, operating results, financial position and cash flows. The Company records actual or potential litigation-related losses in accordance with ASC Topic 450. As of September 30, 2011 and June 30, 2011, the Company had recorded $12,286 and $24,624, respectively, of reserves in the Company's financial statements for probable and estimable liabilities related to the litigation-related losses in which the Company was then involved. The Company also has insurance recovery receivables related to the aforementioned litigation-related reserves of $1,775 and $2,645 as of September 30, 2011 and June 30, 2011, respectively. The Company periodically adjusts the amount of such reserves when such actual or potential liabilities are paid or otherwise discharged, new claims arise, or additional relevant information about existing or potential claims becomes available. The Company believes that it is reasonably possible that the amount of potential litigation related liabilities could increase by as much as $7,400, of which $2,600 would be covered by insurance.

Legal Matters

The Company and its subsidiaries are subject to claims and lawsuits typical of those filed against engineering and consulting companies. The Company carries liability insurance, including professional liability insurance, against such claims subject to certain deductibles and policy limits. Except as described herein, management is of the opinion that the resolution of these claims and lawsuits will not likely have a material effect on the Company's operating results, financial position and cash flows.

The Arena Group v. TRC Environmental Corporation and TRC Companies, Inc., District Court Harris County, Texas, 2007. A former landlord of a subsidiary of the Company sued for damages alleging breach of a lease for certain office space in Houston, Texas which the subsidiary vacated. A jury verdict was rendered against the Company and its subsidiary on June 20, 2011. As a result, the Company took a charge in the fourth quarter of its fiscal year ended June 30, 2011 of $17,278 which included the full value of the verdict as well as pre-judgment interest. Subsequently, the Company filed a post-trial motion to disregard the late fee portion of the verdict, which was granted on October 5, 2011. As a result, the previously established reserve was reduced by $11,224. A judgment was entered in the case on October 10, 2011 and the Company is evaluating post-judgment and appellate measures. Interest accrues at 8% per annum on the amount ultimately determined to be payable until paid. Resolution of this matter may have a significant impact on the Company's cash flows, however the Company believes that existing cash resources, cash forecasted to be generated from operations and availability under its credit facility are adequate to meet this obligation.

In re: World Trade Center Lower Manhattan Disaster Site Litigation, United States District Court for the Southern District of New York, 2006. A subsidiary of the Company has been named as a defendant (along with a number of other defendants) in a number of cases which are pending in the United States District Court for the Southern District of New York and are styled under the caption "In Re World Trade Center Lower Manhattan Disaster Site Litigation." The Complaints allege that the plaintiffs were workers involved in construction, demolition, excavation, debris removal and clean-up in the buildings surrounding the World Trade Center site, allege that plaintiffs were injured and seek unspecified damages for those injuries. The Company believes the subsidiary has meritorious defenses and is adequately insured, however an adverse determination in this matter could have a material effect on the Company's business, operating results, financial position and cash flows.

The Company records actual or potential litigation-related losses in accordance with ASC Topic 450. As of September 30, 2011 and June 30, 2011, the Company had recorded $12,286 and $24,624, respectively, of reserves in the Company's financial statements for probable and estimable liabilities related to the litigation-related losses in which the Company was then involved. The Company also has insurance recovery receivables related to the aforementioned litigation-related reserves of $1,775 and $2,645 as of September 30, 2011 and June 30, 2011, respectively.

The Company periodically adjusts the amount of such reserves when such actual or potential liabilities are paid or otherwise discharged, new claims arise, or additional relevant information about existing or potential claims becomes available. The Company believes that it is reasonably possible that the amount of potential litigation related liabilities could increase by as much as $7,400, of which $2,600 would be covered by insurance.