Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Consolidated Statements of Comprehensive Earnings
Net earnings	$ 36,146	$ 46,532	$ 14,448
Other comprehensive earnings (loss):
Changes in fair market value of derivatives, net of tax	(509)	795	110
Changes in unrealized pension cost, net of tax	6,439	(1,830)	13,687
Cumulative translation adjustment, net of tax	83	(311)	437
Other comprehensive earnings (loss)	6,013	(1,346)	14,234
Comprehensive earnings	$ 42,159	$ 45,186	$ 28,682

Amount after tax of increase (decrease) in equity from transactions and other events and circumstances from net income and other comprehensive income, attributable to parent entity. Excludes changes in equity resulting from investments by owners and distributions to owners.

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