Variable Interest Entities (Details) $ in Thousands	3 Months Ended				6 Months Ended
	Jun. 30, 2020 USD ($)	Mar. 31, 2020 USD ($)	Jun. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Jun. 30, 2020 USD ($) variable_interest_entity	Jun. 30, 2019 USD ($)	Dec. 31, 2019 USD ($)	Dec. 31, 2013 patent
Variable Interest Entity [Line Items]
Assets	$ 1,538,765				$ 1,538,765		$ 1,612,082
Liabilities	748,059				748,059		825,801
Cash and cash equivalents	670,292		$ 531,698		670,292	$ 531,698	745,491
Patents, net	447,194				447,194		436,339
Accounts receivable	19,380				19,380		28,272
Other non-currents assets	78,744				78,744		76,026
Noncontrolling interests	(1,660)	$ (1,777)	(1,365)	$ (1,411)	(3,437)	(2,776)
Chordant
Variable Interest Entity [Line Items]
Noncontrolling interests	200		400		500	700
Convida
Variable Interest Entity [Line Items]
Noncontrolling interests	1,500		$ 1,000		$ 2,900	$ 2,100
Primary Beneficiary
Variable Interest Entity [Line Items]
Number of variable interest entities | variable_interest_entity					3
Assets	62,700				$ 62,700		60,600
Liabilities	5,300				5,300		5,400
Cash and cash equivalents	22,300				22,300		18,500
Accounts receivable and prepaid assets	2,300				2,300
Patents, net	$ 38,100				$ 38,100		39,300
Accounts receivable							1,700
Other non-currents assets							$ 1,300
Number of patents (more than) | patent								500