Summary of Significant Accounting Policies Recently Adopted Accounting Standards (Details) - USD ($) $ in Thousands		3 Months Ended
	Oct. 01, 2018	Dec. 31, 2018	Dec. 31, 2017	Sep. 30, 2018
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts Receivable, Net, Current		$ 337,829		$ 347,873
Prepaid expenses and other current assets		197,414		94,814
Other assets		260,228		141,761
Deferred Revenue, Current		287,242		330,689
Deferred revenue, net of current portion		441,283		434,316
Deferred tax liabilities		66,386		49,931
Other liabilities		103,797		93,593
Hosting		259,588	$ 257,979
Product and licensing		157,997	124,748
Maintenance and support		76,069	64,497
Total revenues		493,654	447,224
Hosting Cost		163,170	171,527
Product and licensing		32,750	13,772
Cost of Sales, Maintenance and Support		7,761	9,425
Amortization of intangible assets			13,514
Cost of Goods and Services Sold		213,438	208,238
Sales and marketing		75,359	80,560
Provision (benefit) for income taxes		986	$ (78,969)
New Accounting Pronouncement or Change in Accounting Principle, Cumulative Effect of Change on Equity or Net Assets				230,000
Accumulated deficit		(488,332)		$ (740,837)
Deferred Revenue [Domain]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 70,000
Other Assets [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	180,000
Accounts Receivable [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	30,000	31,567
Deferred Project Costs [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	30,000
Deferred Tax Asset [Domain]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification	$ 20,000	25,916
Prepaid Expenses and Other Current Assets [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(65,205)
Other Assets [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(139,529)
Deferred revenue, current [Domain]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		86,097
Deferred Revenue [Domain]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		1,376
Other Noncurrent Liabilities [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(8,742)
Retained Earnings [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(245,441)
ASC 605
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
Accounts Receivable, Net, Current		369,396
Prepaid expenses and other current assets		132,209
Other assets		120,699
Deferred Revenue, Current		373,339
Deferred revenue, net of current portion		442,659
Deferred tax liabilities		40,470
Other liabilities		95,055
Hosting		267,624
Product and licensing		135,269
Maintenance and support		60,739
Total revenues		463,632
Hosting Cost		159,232
Product and licensing		14,720
Cost of Sales, Maintenance and Support		8,527
Amortization of intangible assets		9,757
Cost of Goods and Services Sold		192,236
Sales and marketing		76,881
Provision (benefit) for income taxes		576
Accumulated deficit		(733,773)
Cost of professional services and hosting
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		8,036
Cost of product and licensing
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(22,728)
Cost of maintenance and support
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(15,330)
Sales Revenue, Net [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(30,022)
Cost, professional services and hosting [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(3,938)
Cost, product and licensing [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(18,030)
Cost, maintenance and support [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		766
Cost, amortization [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		0
Cost of Sales [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		(21,202)
Sales and marketing
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		1,522
Provision (benefit) for income taxes [Member]
Revenue, Initial Application Period Cumulative Effect Transition [Line Items]
New Accounting Pronouncement or Change in Accounting Principle, Effect of Adoption, Quantification		$ (410)