Earnings per Share (Tables)

12 Months Ended

Oct. 03, 2021

Earnings Per Share [Abstract]

Schedule of number of weighted-average shares used to compute basic and diluted EPS

The following table sets forth the number of weighted-average shares used to compute basic and diluted EPS:

	Fiscal Year Ended
	October 3, 2021		September 27, 2020		September 29, 2019
	(in thousands, except per share data)
Net income attributable to Tetra Tech	$	232,810	$	173,859	$	158,668
Weighted-average common shares outstanding – basic	54,078		54,235		54,986
Effect of diluted stock options and unvested restricted stock	597		787		950
Weighted-average common stock outstanding – diluted	54,675		55,022		55,936
Earnings per share attributable to Tetra Tech:
Basic	$	4.31	$	3.21	$	2.89
Diluted	$	4.26	$	3.16	$	2.84