Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017	Jun. 30, 2018	Jun. 30, 2017
Statement of Comprehensive Income [Abstract]
Net income	$ 16,724	$ 12,105	$ 26,148	$ 18,985
Other comprehensive (loss)/income
Change in unrealized gains/(losses) on available-for-sale debt securities, net of tax	17	(31)	477	(134)
Foreign currency translation adjustment	(719)	194	(307)	439
Other comprehensive (loss)/income	(702)	163	170	305
Comprehensive income	$ 16,022	$ 12,268	$ 26,318	$ 19,290

The portion of profit or loss for the period, net of income taxes, which is attributable to the parent.

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