Net Income Per Share Attributable to Common Stockholders - Computation of Basic and Diluted Earnings per Share (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended
	Jan. 02, 2021	Dec. 28, 2019
Numerator:
Net income	$ 132,292	$ 70,775
Denominator:
Weighted-average shares of common stock - basic (in shares)	115,610,523	108,984,683
Weighted-average shares of common stock - diluted (in shares)	130,644,147	118,415,968
Net income attributable to common stockholders:
Net income (loss) per share attributable to common stockholders - basic (in USD per share)	$ 1.14	$ 0.65
Net income (loss) per share attributable to common stockholders - diluted (in USD per share)	$ 1.01	$ 0.60
Stock Options
Denominator:
Effect of potentially dilutive stock options and RSUs (in shares)	8,105,916	6,751,412
Restricted Stock Units
Denominator:
Effect of potentially dilutive stock options and RSUs (in shares)	6,927,708	2,679,873