Stockholders' Equity - Schedule of amounts reclassified from AOCI (Details) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2020	Mar. 31, 2019
Changes in Accumulated Other Comprehensive Income (Loss)
Investment income, net	$ 97	$ 6,655
Foreign currency translation gain (loss)	25	0
Reclassification Out Of Accumulated Other Comprehensive Income
Changes in Accumulated Other Comprehensive Income (Loss)
Total reclassifications	(25)	(125)
Reclassification Out Of Accumulated Other Comprehensive Income \| Unrealized Gain (Loss) on Marketable Securities
Changes in Accumulated Other Comprehensive Income (Loss)
Investment income, net	0	125
Foreign currency translation gain (loss)	$ 25	$ 0

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