CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2018	Dec. 31, 2017	Dec. 31, 2016
Statement of Comprehensive Income [Abstract]
Net income	$ 135,413	$ 84,402	$ 65,991
Other comprehensive loss:
Unrealized loss on available-for-sale securities, net of tax	(4)	(2)	(3)
Comprehensive income	$ 135,409	$ 84,400	$ 65,988

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

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