Disaggregation of Revenue (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2018	Mar. 31, 2017
Software licenses	$ 110,046	$ 141,908
Maintenance and service	172,827	111,497
Total revenue	282,873	253,405
Lease License Revenue
Software licenses	48,772	93,634
Perpetual License Revenue
Software licenses	61,274	48,274
Maintenance Revenue
Maintenance and service	163,896	104,406
Service Revenue
Maintenance and service	8,931	$ 7,091
Previous Accounting Guidance
Software licenses	154,857
Maintenance and service	129,712
Total revenue	284,569
Previous Accounting Guidance \| Lease License Revenue
Software licenses	101,789
Previous Accounting Guidance \| Perpetual License Revenue
Software licenses	53,068
Previous Accounting Guidance \| Maintenance Revenue
Maintenance and service	120,762
Previous Accounting Guidance \| Service Revenue
Maintenance and service	$ 8,950

Revenue earned during the period relating to consideration received from another party for the right to use, but not own, certain of the entity's intangible assets. Licensing arrangements include, but are not limited to, rights to use a patent, copyright, technology, manufacturing process, software or trademark. Licensing fees are generally, but not always, fixed as to amount and not dependent upon the revenue generated by the licensing party. An entity may receive licensing fees for licenses that also generate royalty payments to the entity.

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(e))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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Revenue derived from maintenance services provided under contracts or arrangements with clients. For example, it may include the maintenance of software, plant and equipment, and facilities.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1(d))
-URI http://asc.fasb.org/extlink&oid=63488584&loc=d3e20235-122688

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- Definition

Amount of revenue recognized from goods sold, services rendered, insurance premiums, or other activities that constitute an earning process. Includes, but is not limited to, investment and interest income before deduction of interest expense when recognized as a component of revenue, and sales and trading gain (loss).

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 225
-SubTopic 10
-Section S99
-Paragraph 2
-Subparagraph (SX 210.5-03.1)
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