Stock-Based Compensation (Tables)

9 Months Ended

Jun. 30, 2018

Disclosure of Compensation Related Costs, Share-based Payments [Abstract]

Stock-Based Compensation Expense in Consolidated Statements of Operations

The following presents stock-based compensation expense in the Company’s Consolidated Statements of Income:



	Three Months Ended				Nine Months Ended
	June 30, 2018		July 1, 2017		June 30, 2018		July 1, 2017
Cost of revenues	$	1.8	$	2.3	$	6.5	$	8.7
Research and development	2.2		2.2		7.6		9.1
Selling and marketing	2.6		3.4		8.0		9.3
General and administrative	10.6		6.5		29.7		26.3
Restructuring	—		—		1.3		—
	$	17.2	$	14.4	$	53.1	$	53.4

Weighted-Average Assumptions Utilized to Value Stock Options

The Company uses a binomial model to determine the fair value of its stock options. The weighted-average assumptions utilized to value these stock options are indicated in the following table:



	Three Months Ended				Nine Months Ended
	June 30, 2018	July 1, 2017			June 30, 2018			July 1, 2017
Risk-free interest rate	**	1.8		%	2.1		%	1.8		%
Expected volatility	**	36.5		%	35.3		%	36.6		%
Expected life (in years)	**	4.7			4.7			4.7
Dividend yield	**	—			—			—
Weighted average fair value of options granted	**	$	14.40		$	12.98		$	12.33

** There were no stock options granted in the three months ended June 30, 2018.