Condensed Consolidated Balance Sheets (Unaudited) (Parenthetical) - USD ($) $ in Thousands	Jun. 26, 2020	Sep. 30, 2019
Statement of Financial Position [Abstract]
Allowance for doubtful accounts	$ 4,321	$ 2,608
Common stock, par value (in dollars per share)	$ 0.01	$ 0.01
Common stock, shares authorized (shares)	1,000,000,000	1,000,000,000
Common stock, shares issued (shares)	47,259,994	46,955,163
Common stock, shares outstanding (shares)	47,259,994	46,955,163
Treasury stock (shares)	260,900	260,900

Amount of allowance for credit loss on accounts receivable, classified as current.

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