Share - Based Compensation Plans (Tables)

12 Months Ended

Oct. 02, 2020

Share-based Payment Arrangement [Abstract]

Effects of Stock-Based Compensation Expense Related to Stock-Based Awards to Employees and Nonemployees

The following table shows a summary of share-based compensation expense included in the Consolidated Statements of Operations during the periods presented (in thousands): 

	Fiscal Years
	2020		2019		2018
Cost of revenue	$	3,609	$	2,936	$	3,869
Research and development	12,794		8,551		13,448
Selling, general and administrative	19,271		12,305		14,620
Total	$	35,674	$	23,792	$	31,937

Summary of Stock Option Activity

A summary of stock option activity for fiscal year 2020 is as follows (in thousands, except per share amounts and contractual term):

	Number of Shares	Weighted-Average Exercise Price per Share		Weighted-Average Remaining Contractual Term (in Years)	Aggregate Intrinsic Value
Options outstanding - September 27, 2019	376	$	13.58
Granted	—	—
Exercised	(51)	3.70
Forfeited, canceled or expired	—	—
Options outstanding - October 2, 2020	325	$	15.12	6.99	$	6,071
Options vested and expected to vest - October 2, 2020	325	$	15.12	6.99	$	6,071
Options exercisable - October 2, 2020	40	$	17.50	3.57	$	652

Weighted Average Assumptions used for Calculating Fair Value of Stock Options Granted

The weighted average Monte Carlo input assumptions used for calculating the fair value of these market-based stock options are as follows:

	Fiscal Years
	2019		2018
Risk-free interest rate	2.8	%	2.3	%
Expected term (years)	3.9		3.4
Expected volatility	51.9	%	45.8	%
Target price	$53.87		$98.99

The assumptions used to value the awards are as follows:

	Fiscal Year
	2019
Risk free interest rate	1.9	%
Years to maturity	3.33
Expected volatility rate	61.5	%
Dividend yield	—

Summary of Restricted Stock Awards and Unit Activity

A summary of restricted stock awards and units activity for fiscal year 2020 is as follows (in thousands):

	Number of Shares	Weighted-Average Grant Date Fair Value
Issued and unvested - September 27, 2019	2,615	$	21.81
Granted	1,210	22.07
Vested	(648)	26.24
Forfeited, canceled or expired	(389)	22.18
Issued and unvested - October 2, 2020	2,788	20.84