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Intangible Assets and Goodwill (Details 2) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended	9 Months Ended			12 Months Ended
	Mar. 31, 2020	Jun. 30, 2020	Sep. 30, 2020	Sep. 30, 2019	Sep. 30, 2018	Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Components of intangible assets
Intangible Assets, Gross						$ 301,982	$ 301,982
Accumulated Amortization						(265,495)	(247,082)
Finite-lived intangible assets						34,887
In-process research and development						1,600
Intangible assets, net	$ 50,208	$ 45,624	$ 41,052	$ 35,362		36,487	54,900
Amortization expense for intangible assets	$ 4,692	$ 9,276	$ 13,848	$ 13,096	$ 24,352	$ 18,413	17,058	$ 29,341
Minimum
Components of intangible assets
Useful life (in years)						6 months
Maximum
Components of intangible assets
Useful life (in years)						10 years
Existing technology
Components of intangible assets
Gross Carrying Amount						$ 263,789	262,789
Accumulated Amortization						(230,950)	(213,354)
Finite-lived intangible assets						$ 32,839	$ 49,435
Existing technology \| Minimum
Components of intangible assets
Useful life (in years)						3 years	3 years
Existing technology \| Maximum
Components of intangible assets
Useful life (in years)						10 years	10 years
Customer contracts and contractual relationships
Components of intangible assets
Gross Carrying Amount						$ 36,293	$ 36,293
Accumulated Amortization						(34,245)	(33,428)
Finite-lived intangible assets						$ 2,048	$ 2,865
Customer contracts and contractual relationships \| Minimum
Components of intangible assets
Useful life (in years)						6 months	6 months
Customer contracts and contractual relationships \| Maximum
Components of intangible assets
Useful life (in years)						10 years	10 years
Non-competition agreements
Components of intangible assets
Gross Carrying Amount						$ 300	$ 300
Accumulated Amortization						(300)	(300)
Finite-lived intangible assets						$ 0	$ 0
Useful life (in years)						3 years	3 years
In-process research and development
Components of intangible assets
In-process research and development						$ 1,600	$ 2,600
Payments and Ticketing business
Components of intangible assets
Disposal of intangible assets, noncurrent							$ 20,700