Litigation (Details) $ in Thousands							3 Months Ended
	Mar. 23, 2020 USD ($)	Sep. 20, 2018 USD ($)	Aug. 31, 2018 USD ($) $ / Device	Sep. 29, 2017 USD ($) $ / Device	Sep. 30, 2016 USD ($) Patent	Nov. 06, 2012 USD ($) Patent	Mar. 31, 2020 USD ($)
Litigation [Abstract]
Total cash received							$ 454,034
VirnetX Inc. v. Apple, Inc. (Case 6:12-CV-00855-LED) ("Apple II") [Member]
Litigation [Abstract]
Amount of damages awarded in patent infringement case		$ 595,900	$ 502,600
Royalty rate per device used in calculating infringement damages | $ / Device			1.20
Additional amount granted in agreed bill of costs, attorney fees, and prejudgment interest		$ 93,300
McKool Smith P.C. v. VirnetX, Inc., AAA (Case No. 01-20-0003-7975) [Member]
Litigation [Abstract]
Contingency fee sought by plaintiff	$ 36,300
Contingency fee as percentage of payment	8.00%
Positive Outcome of Litigation [Member] | VirnetX Inc. v. Cisco Systems, Inc. et al. (Case 6:10-CV-00417-LED) ("Apple I") [Member]
Litigation [Abstract]
Amount of damages awarded in patent infringement case				$ 439,700	$ 302,400
Number of patents allegedly infringed upon by Apple, Inc. | Patent					4	4
Enhanced damages				41,300
Costs, fees and interest				$ 96,000
Total cash received	$ 454,034
Positive Outcome of Litigation [Member] | VirnetX Inc. v. Cisco Systems, Inc. et al. (Case 6:10-CV-00417-LED) ("Apple I") [Member] | Minimum [Member]
Litigation [Abstract]
Amount of damages awarded in patent infringement case						$ 368,000
Royalty rate per device used in calculating infringement damages | $ / Device				1.20
Positive Outcome of Litigation [Member] | VirnetX Inc. v. Cisco Systems, Inc. et al. (Case 6:10-CV-00417-LED) ("Apple I") [Member] | Maximum [Member]
Litigation [Abstract]
Royalty rate per device used in calculating infringement damages | $ / Device				1.80