Employee Benefit Plans - Obligations and Funded Status (Details) - USD ($) $ in Thousands	12 Months Ended
	Aug. 30, 2025	Aug. 31, 2024	Aug. 26, 2023
UniFirst Plan
Change in benefit obligation:
Projected benefit obligation, beginning of year	$ 3,609	$ 3,549
Service cost	73	74	$ 73
Interest cost	148	159	147
Actuarial loss (gain)	3	(28)
Benefits paid	(37)	(145)
Settlements	(792)
Projected benefit obligation, end of year	3,004	3,609	3,549
Change in plan assets:
Fair value of plan assets, beginning of year	3,108	2,986
Actual return on plan assets	27	20
Employer Contributions	168	247
Benefits paid	(37)	(145)
Settlements	(792)
Fair value of plan assets, end of year	2,474	3,108	2,986
Funded status (net amount recognized):	(530)	(501)
SERP
Change in benefit obligation:
Projected benefit obligation, beginning of year	25,880	25,119
Service cost	390	405	486
Interest cost	1,239	1,255	1,191
Actuarial loss (gain)	(2,549)	465
Benefits paid	(1,481)	(1,364)
Projected benefit obligation, end of year	23,479	25,880	$ 25,119
Change in plan assets:
Funded status (net amount recognized):	$ (23,479)	$ (25,880)