Consolidated Condensed Statements of Comprehensive Income - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2019	Jun. 30, 2018	Jun. 30, 2019	Jun. 30, 2018
Statement Of Income And Comprehensive Income [Abstract]
Net earnings	$ 11,358	$ 6,154	$ 22,182	$ 13,700
Other comprehensive income:
Foreign currency translation adjustments	395	(808)	137	(387)
Pension and postretirement benefits, net of tax	360	5,711	349	5,772
Comprehensive income	$ 12,113	$ 11,057	$ 22,668	$ 19,085

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

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