Pay vs Performance Disclosure - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Jun. 29, 2025	Jun. 30, 2024	Jun. 29, 2025	Jun. 30, 2024
Pay vs Performance Disclosure
Net income attributable to Tetra Tech	$ 113,844	$ 85,810	$ 119,979	$ 237,228

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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+ Details