Stock-based Compensation (Tables)

12 Months Ended

Sep. 30, 2019

Disclosure Of Compensation Related Costs Sharebased Payments [Abstract]

Fair Values of Options, Black-Scholes Option-Pricing Model, Weighted-Average Assumptions

The fair values of the options granted for the year ended September 30, 2019 were estimated on the dates of grants using the Black-Scholes option-pricing model with the following weighted-average assumptions:

	Year Ended September 30,
	2019			2018			2017
Risk-free interest rate		2.86	%		2.10	%		1.97	%
Expected volatility		29.68	%		26.43	%		28.83	%
Expected life (in years)		5.22			5.46			5.30
Dividend yield		-			-			-

Stock Options Outstanding and Activity During the Period

The following table summarizes all stock option activity for the periods presented (in thousands, except share, per share, and time period amounts):

	Options Outstanding			Weighted- Average Exercise Price		Weighted- Average Remaining Contractual Term (Years)		Aggregate Intrinsic Value1
Balance as of September 30, 2018		1,969,037		$	33.08		5.7	$	14,088
Granted		674,015			27.67
Exercised		(183,347	)		18.08
Canceled/Forfeited		(117,108	)		35.18
Expired		(3,108	)		26.74
Balance as of September 30, 2019		2,339,489		$	32.61		6.1	$	12,034
Vested and expected to vest after September 30, 2019		2,305,869		$	32.62		6.1	$	11,870
Exercisable as of September 30, 2019		1,484,158		$	31.54		4.5	$	8,343

^{___________________________________________________________________________}

¹ Aggregate intrinsic value as represents the difference between the closing fair value of the underlying common stock and the exercise price of outstanding, in-the-money options on the date of measurement.

Stock Option Grants, Vesting, and Exercises

The following table summarizes additional information on stock options for the periods presented (in thousands, except per share amounts):

	Year Ended September 30,
	2019		2018		2017
Weighted-average fair value of stock options granted	$	8.91	$	15.86	$	14.21
Total grant date fair value of stock options vested		3,850		4,208		5,541
Total intrinsic value of stock options exercised		2,849		9,645		10,941

Restricted Shares and Units Outstanding and Activity During the Period

The following table summarizes all restricted stock unit activity for the periods presented:

	RSUs Outstanding			Weighted-Average Grant Date Fair Value
Balance as of September 30, 2018		934,023		$	47.00
Granted		722,531			28.02
Released		(375,084	)		40.65
Canceled/Forfeited		(158,112	)		42.92
Balance as of September 30, 2019		1,123,358		$	37.48
Vested and expected to vest after September 30, 2019		908,892		$	39.41

Schedule Of Restricted Stock Units Additional Information

The following table summarizes additional information on RSUs for the period presented (in thousands, except share and per share amounts):

	Year Ended September 30,
	2019		2018		2017
Weighted-average fair value of RSUs granted	$	28.02	$	57.40	$	47.31
Total grant date fair value of RSUs vested		16,087		6,656		4,562
Total intrinsic value of RSUs released		11,460		11,041		6,079