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Variable Interest Entities (Details) $ in Thousands	3 Months Ended					9 Months Ended
Variable Interest Entities (Details) $ in Thousands	Sep. 30, 2019 USD ($)	Mar. 31, 2019 USD ($)	Sep. 30, 2018 USD ($)	Jun. 30, 2018 USD ($)	Mar. 31, 2018 USD ($)	Sep. 30, 2019 USD ($) variable_interest_entity	Sep. 30, 2018 USD ($)	Dec. 31, 2018 USD ($)	Dec. 31, 2013 patent
Variable Interest Entity [Line Items]
Variable interest entities assets	$ 41,300					$ 41,300		$ 29,900
Variable interest entities liabilities	3,800					3,800		6,100
Noncontrolling interests	(1,399)	$ (1,411)	$ (1,642)	$ (1,190)	$ (1,501)	(4,175)	$ (4,333)
Cash and Cash Equivalents
Variable Interest Entity [Line Items]
Variable interest entities assets	20,800					20,800		11,700
Accounts Receivable
Variable Interest Entity [Line Items]
Variable interest entities assets	1,500					1,500		1,300
Patents
Variable Interest Entity [Line Items]
Variable interest entities assets	17,700					17,700		14,400
Other Noncurrent Assets
Variable Interest Entity [Line Items]
Variable interest entities assets	1,300					1,300		$ 2,500
Chordant
Variable Interest Entity [Line Items]
Noncontrolling interests	500					1,200
Convida
Variable Interest Entity [Line Items]
Noncontrolling interests	$ 900					$ 3,000
Primary Beneficiary
Variable Interest Entity [Line Items]
Number of variable interest entities \| variable_interest_entity						3
Number of patents (more than) \| patent									500