Significant Accounting Policies - Impact of Adoption of ASU 2014-09 (Details) - USD ($) $ / shares in Units, $ in Thousands	3 Months Ended			9 Months Ended
	Sep. 30, 2018	Sep. 30, 2017		Sep. 30, 2018	Sep. 30, 2017		Jan. 01, 2018	Dec. 31, 2017
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	$ 732,476	$ 690,925	[1]	$ 2,172,033	$ 2,046,829	[1]
Total cost of net revenues	103,917	105,937		320,952	317,707
Gross margin	628,559	584,988		1,851,081	1,729,122
Total operating expenses	463,780	448,275		1,375,592	1,347,824
Income from operations	164,779	136,713		475,489	381,298
Net income	$ 158,857	$ 126,720		$ 409,949	$ 263,170
Basic earnings per share (in dollars per share)	$ 1.18	$ 0.84		$ 3.00	$ 1.73
Diluted earnings per share (in dollars per share)	$ 1.08	$ 0.82		$ 2.80	$ 1.68
Prepaid and other current assets	$ 229,188			$ 229,188				$ 147,330
Other assets	116,031			116,031				52,685
Deferred tax assets, net	127,703			127,703				152,362
Total assets	5,436,527			5,436,527				5,820,176
Other liabilities	144,892			144,892				121,936
Current portion of deferred revenues	1,212,280			1,212,280			$ 1,250,000	1,308,474
Long-term portion of deferred revenues	467,722			467,722			512,800	555,769
Total liabilities	4,664,021			4,664,021
Retained earnings	4,052,211			4,052,211				$ 3,509,484
Balances without adoption of ASC 606 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	736,055			2,185,299
Total cost of net revenues	103,739			319,673
Gross margin	632,316			1,865,626
Total operating expenses	472,715			1,398,446
Income from operations	159,601			467,180
Net income	$ 154,513			$ 404,710
Basic earnings per share (in dollars per share)	$ 1.14			$ 2.96
Diluted earnings per share (in dollars per share)	$ 1.05			$ 2.76
Prepaid and other current assets	$ 202,998			$ 202,998
Other assets	48,648			48,648
Deferred tax assets, net	159,181			159,181
Total assets	5,374,432			5,374,432
Other liabilities	131,807			131,807
Current portion of deferred revenues	1,260,727			1,260,727
Long-term portion of deferred revenues	507,648			507,648
Total liabilities	4,739,309			4,739,309
Retained earnings	3,914,828			3,914,828
Accounting Standards Update 2014-09 [Member] | Effect of Change Higher/(Lower) [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Revenue	(3,579)			(13,266)
Total cost of net revenues	178			1,279
Gross margin	(3,757)			(14,545)
Total operating expenses	(8,935)			(22,854)
Income from operations	5,178			8,309
Net income	$ 4,344			$ 5,239
Basic earnings per share (in dollars per share)	$ 0.04			$ 0.04
Diluted earnings per share (in dollars per share)	$ 0.03			$ 0.04
Prepaid and other current assets	$ 26,190			$ 26,190
Other assets	67,383			67,383
Deferred tax assets, net	(31,478)			(31,478)
Total assets	62,095			62,095
Other liabilities	13,085			13,085
Current portion of deferred revenues	(48,447)			(48,447)
Long-term portion of deferred revenues	(39,926)			(39,926)
Total liabilities	(75,288)			(75,288)
Retained earnings	137,383			137,383			130,700
Contract assets							$ 7,300
Prepaid Expenses and Other Current Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract acquisition costs	38,600			38,600
Prepaid Expenses and Other Current Assets [Member] | Balances without adoption of ASC 606 [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract acquisition costs	14,200			14,200
Other Noncurrent Assets [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Contract acquisition costs	64,900			64,900
Other Noncurrent Liabilities [Member]
New Accounting Pronouncements or Change in Accounting Principle [Line Items]
Deferred tax liabilities	$ 53,200			$ 53,200

[1] Workspace Services revenues are primarily comprised of sales from the Company’s application virtualization solutions, which include XenDesktop and XenApp, the Company's enterprise mobility management solutions, which include XenMobile, and Citrix Workspace, and related license updates, maintenance and subscription offerings.