Consolidated Statements of Comprehensive Earnings - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016	Dec. 31, 2015
Consolidated Statements of Comprehensive Earnings
Net earnings	$ 14,448	$ 34,380	$ 6,954
Other comprehensive earnings (loss):
Changes in fair market value of hedges, net of tax	110	553	157
Changes in unrealized pension cost, net of tax	13,687	6,412	6,809
Cumulative translation adjustment, net of tax	437	(1,154)	(1,738)
Other comprehensive earnings	14,234	5,811	5,228
Comprehensive earnings	$ 28,682	$ 40,191	$ 12,182

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

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Amount after tax and reclassification adjustments, of increase (decrease) in accumulated gain (loss) from derivative instruments designated and qualifying as the effective portion of cash flow hedges and an entity's share of an equity investee's increase (decrease) in deferred hedging gain (loss).

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Amount after tax and reclassification adjustments of gain (loss) on foreign currency translation adjustments, foreign currency transactions designated and effective as economic hedges of a net investment in a foreign entity and intra-entity foreign currency transactions that are of a long-term-investment nature.

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Amount after tax of other comprehensive income (loss) attributable to parent entity.

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