Reportable Segments - Geographic Information (Details) - USD ($) $ in Thousands	3 Months Ended								12 Months Ended
	Oct. 03, 2021	Jun. 27, 2021	Mar. 28, 2021	Dec. 27, 2020	Sep. 27, 2020	Jun. 28, 2020	Mar. 29, 2020	Dec. 29, 2019	Oct. 03, 2021	Sep. 27, 2020	Sep. 29, 2019
Reportable Segments
Revenue	$ 892,012	$ 801,633	$ 754,764	$ 765,104	$ 753,364	$ 709,771	$ 734,133	$ 797,623	$ 3,213,513	$ 2,994,891	$ 3,107,348
Long-lived assets	303,460				339,281				303,460	339,281
United States
Reportable Segments
Revenue									2,256,086	2,107,459	2,247,780
Long-lived assets	215,689				230,933				215,689	230,933
Foreign countries
Reportable Segments
Revenue									957,427	887,432	$ 859,568
Long-lived assets	$ 87,771				$ 108,348				$ 87,771	$ 108,348