Revenue - Remaining Performance Obligations (Details) $ in Thousands	Jun. 30, 2018 USD ($)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	$ 1,852,550
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01 | Subscription [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	275,424
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2018-07-01 | Support and Services [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	1,577,126
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	84,144
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Subscription [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	26,255
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2020-01-01 | Support and Services [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	57,889
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	3,969
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Subscription [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	530
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: 2022-01-01 | Support and Services [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	3,439
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil)
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	1,940,663
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Subscription [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	302,209
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction, Start Date [Axis]: (nil) | Support and Services [Member]
Revenue, Remaining Performance Obligation, Expected Timing of Satisfaction [Line Items]
Total net revenues	$ 1,638,454