Equity Incentive Plan (Tables)

12 Months Ended

Sep. 30, 2017

Share-based Compensation, Allocation and Classification in Financial Statements [Abstract]

Total Stock Based Compensation Expense

The following table shows total stock-based compensation expense recorded from our stock-based awards as reflected in our Consolidated Statements of Operations: 

	Year ended September 30,
	2017		2016		2015
	(in thousands)
Cost of license subscription revenue	$	1,379	$	805	$	521
Cost of support revenue	5,116		4,593		3,775
Cost of professional services revenue	6,116		5,393		5,871
Sales and marketing	15,373		14,659		14,189
Research and development	13,968		10,174		11,623
General and administrative	34,756		30,372		14,203
Total stock-based compensation expense	$	76,708	$	65,996	$	50,182

Restricted Stock And Restricted Stock Unit Grants

	Shares		Weighted Average   Grant Date   Fair Value		Aggregate Intrinsic Value as of September 30, 2017
Restricted stock unit activity for the year ended September 30, 2017	(in thousands except grant date fair value data)
Balance of nonvested outstanding restricted stock units October 1, 2016	3,776		$	37.30
Granted	1,946		$	51.27
Vested	(1,586	)	$	36.05
Forfeited or not earned	(649	)	$	37.83
Balance of nonvested outstanding restricted stock units September 30, 2017	3,487		$	45.57	$	196,230

	Restricted Stock Units
Restricted stock unit grants	TSR Units (1)	Performance-based RSUs (2)	Service-based RSUs (3)
	(Number of Units in thousands)
Year ended September 30, 2017	358	325	1,263

(1) The TSR units were granted to our executive officers pursuant to the terms described below.

(2) The performance-based RSUs were issued to employees, our executive officers, our directors and a consultant. Executive officers may earn up to one or, for our CEO, two times the number of time-based RSUs (up to a maximum of 325 thousand shares) if certain performance conditions are met. Of the service-based RSUs, approximately 108 thousand shares will vest in one installment on or about the anniversary of the date of grant. Approximately 217 thousand shares will vest in two substantially equal annual installments on or about the anniversary of the date of grant. All other service-based RSUs will vest in three substantially equal annual installments on or about the anniversary of the date of grant. The performance-based RSUs will vest in three substantially equal installments on the later of November 15, 2017, November 15, 2018 and November 15, 2019, or the date the Compensation Committee determines the extent to which the applicable performance criteria have been achieved.

(3) The service-based RSUs were granted to employees, our executive officers and our directors. All service-based RSUs will vest in three substantially equal annual installments on or about the anniversary of the date of grant.

Schedule of Share-based Payment Award, Employee Stock Purchase Plan, Valuation Assumptions [Table Text Block]

The significant assumptions used in the Monte Carlo simulation model were as follows:

Average volatility of peer group	29.3	%
Risk free interest rate	0.99	%
Dividend yield	—	%

Value Of Stock Option And Stock-Based Award Activity

	Year ended September 30,
	2017		2016		2015
Value of stock option and stock-based award activity	(in thousands)
Total intrinsic value of stock options exercised	$	—	$	88	$	182
Total fair value of restricted stock unit awards vested	$	78,573	$	63,655	$	84,189