CONSOLIDATED STATEMENTS OF COMPREHENSIVE INCOME (Unaudited) - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net income	$ 4,214	$ 21,336
Comprehensive income	$ 4,214	$ 21,336

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

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