Description of Business and Basis of Presentation Reclassification (Details) $ in Thousands	12 Months Ended
	Sep. 30, 2016 USD ($) revenue_category	Sep. 30, 2015 USD ($) revenue_category	Sep. 30, 2014 USD ($) revenue_category
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue, Net	$ 1,140,533	$ 1,255,242	$ 1,356,967
Number of Revenue Categories | revenue_category	4	3	3
Number of Cost of Revenue Categories | revenue_category	2	3	3
Perpetual license	$ 173,467	$ 282,760	$ 362,602
Subscription	118,322	65,239	27,137
Cost of software revenue	$ 155,439	135,992	129,708
From License and Subscription to Perpetual License [Member] [Domain] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Perpetual license		282,800	362,600
From License and Subscription to Subscription License [Member] [Domain] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Subscription		65,200	27,100
From License and Subscription to Software [Member] [Domain] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cost of software revenue		53,200	45,000
From Support to Software [Member] [Domain] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cost of software revenue		82,800	84,700
From General and Administration to Selling and Marketing [Member] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Cost of software revenue		8,000	$ 10,000
Out of Period Correction [Member] | Restatement Adjustment [Member]
Error Corrections and Prior Period Adjustments Restatement [Line Items]
Revenue, Net		$ 6,400