XML 26 R10.htm IDEA: XBRL DOCUMENT
v3.8.0.1

Description of Business | 12 Months Ended
--- | ---
Oct. 01, 2017
Description of Business |
Description of Business | Description of Business We are a leading provider of consulting and engineering services that focuses on water, environment, infrastructure, resource management, energy, and international development. We are a global company that is renowned for our expertise in providing water-related services for public and private clients. We typically begin at the earliest stage of a project by identifying technical solutions and developing execution plans tailored to our clients' needs and resources. Our solutions may span the entire life cycle of consulting and engineering projects and include applied science, data analysis, research, engineering, design, construction management, and operations and maintenance. In fiscal 2017, we managed our operations under three reportable segments. We report our water resources, water and wastewater treatment, environment, and infrastructure engineering activities in the Water, Environment and Infrastructure ("WEI") reportable segment. Our Resource Management and Energy ("RME") reportable segment includes our oil and gas, energy, international development, waste management, remediation, and utilities services. In addition, we report the results of the wind-down of our non-core construction activities in the Remediation and Construction Management ("RCM") reportable segment.

X
- References No definition available. + Details
Name: | ttek_DescriptionOfBusinessDisclosureAbstract
Namespace Prefix: | ttek_
Data Type: | xbrli:stringItemType
Balance Type: | na
Period Type: | duration

X
- Definition The entire disclosure for the nature of an entity's business, major products or services, principal markets including location, and the relative importance of its operations in each business and the basis for the determination, including but not limited to, assets, revenues, or earnings. For an entity that has not commenced principal operations, disclosures about the risks and uncertainties related to the activities in which the entity is currently engaged and an understanding of what those activities are being directed toward. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 275 -URI http://asc.fasb.org/topic&trid=2134479 + Details
Name: | us-gaap_NatureOfOperations
Namespace Prefix: | us-gaap_
Data Type: | nonnum:textBlockItemType
Balance Type: | na
Period Type: | duration