Consolidated Statements of Comprehensive Income (Loss) (Unaudited) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement Of Income And Comprehensive Income [Abstract]
Net income (loss)	$ 2,338	$ (16,279)	$ (33,254)	$ (14,855)
Other comprehensive income (loss), net of tax:
Change in foreign currency translation	467	(318)	301	(288)
Change in fair value of available for sale securities	534	523	311	1,286
Total other comprehensive income (loss)	1,001	205	612	998
Comprehensive income (loss)	$ 3,339	$ (16,074)	$ (32,642)	$ (13,857)

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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