Summary of Significant Accounting Policies (Details) - USD ($)		1 Months Ended	3 Months Ended		6 Months Ended		12 Months Ended
		Nov. 30, 2018	Jun. 30, 2017	Jun. 30, 2016	Jun. 30, 2017	Jun. 30, 2016	Dec. 31, 2016	Nov. 30, 2013
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Operating leases, future minimum payments due			$ 364,000,000		$ 364,000,000
Revenues			471,703,000	$ 341,312,000	888,486,000	$ 647,191,000
Decrease to sales and marketing expense	[1]		(247,224,000)	$ (186,506,000)	$ (459,310,000)	$ (345,116,000)
Accounting Standards Update 2014-09
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Commissions for on premise support and cloud-based subscription period of benefit, amortization period					5 years
Minimum | Accounting Standards Update 2014-09 | Restatement Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues							$ 14,000,000
Decrease to sales and marketing expense							20,000,000
Maximum | Accounting Standards Update 2014-09 | Restatement Adjustment
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenues							19,000,000
Decrease to sales and marketing expense							25,000,000
2018 convertible senior notes
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Face amount of debt			$ 575,000,000		$ 575,000,000		$ 575,000,000	$ 575,000,000.0
Stated interest rate								0.00%
Effective interest rate of the liability component			6.50%	6.50%	6.50%	6.50%
2018 convertible senior notes | Forecast
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Debt discount classified as operating cash outflow		$ 155,300,000
Repayment of debt classified as financing cash outflow		$ 419,700,000

[1] Includes stock-based compensation as follows:   Three Months Ended June 30,   Six Months Ended June 30,   2017   2016   2017   2016 Cost of revenues:               Subscription $ 8,942
  $ 6,951
  $ 16,880
  $ 13,558
Professional services and other 7,617
  6,136
  14,566
  12,895
Sales and marketing 42,287
  32,861
  80,688
  63,859
Research and development 22,731
  21,047
  44,532
  41,580
General and administrative 16,489
  11,070
  31,343
  21,481