Condensed Consolidated Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended
Mar. 31, 2019	Mar. 31, 2018
Statement of Comprehensive Income [Abstract]
Net income	$ 9,720	$ 8,927
Other comprehensive income (loss), net of tax:
Change in Company-sponsored post-employment benefit plan	14	(13)
Comprehensive income	$ 9,734	$ 8,914

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

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