Basis of Presentation

9 Months Ended

Jun. 30, 2019

Organization, Consolidation and Presentation of Financial Statements [Abstract]

Basis of Presentation

Basis of Presentation

The accompanying unaudited interim consolidated financial statements and related notes of Tetra Tech, Inc. (“we,” “us,” “our” or "Tetra Tech") have been prepared in accordance with generally accepted accounting principles in the United States of America (“U.S. GAAP”) for interim financial information and with the instructions to Form 10-Q and Rule 10-01 of Regulation S-X. They do not include all of the information and footnotes required by U.S. GAAP for complete financial statements and, therefore, should be read in conjunction with the audited consolidated financial statements and related notes contained in our Annual Report on Form 10-K for the fiscal year ended September 30, 2018.

These financial statements reflect all normal recurring adjustments that are considered necessary for a fair statement of our financial position, results of operations and cash flows for the interim periods presented. The results of operations and cash flows for any interim period are not necessarily indicative of results for the full year or for future years. Certain reclassifications were made to the prior year to conform to current year presentation.

In May 2014, the Financial Accounting Standards Board (“FASB”) issued ASU 2014-09 ("ASC 606"), "Revenue from Contracts with Customers", which outlines a single comprehensive model for entities to use in accounting for revenue arising from contracts with customers and supersedes most current revenue recognition guidance, including industry-specific guidance. The guidance and the related ASUs were effective for interim and annual reporting periods beginning after December 15, 2017 (first quarter of fiscal 2019 for us). On October 1, 2018, we adopted ASC 606 using the modified retrospective method in which the new guidance was applied retrospectively to contracts that were not substantially completed as of the date of adoption. Results for the reporting period beginning after October 1, 2018 have been presented under ASC 606, while prior period amounts have not been adjusted and continue to be reported in accordance with the previous guidance. See Note 3, "Revenue Recognition" for further discussion of the adoption and the impact on our consolidated financial statements.