Consolidated Statements Of Shareholders' Equity (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2020	Dec. 31, 2019	Dec. 31, 2018
Statement of Stockholders' Equity [Abstract]
Foreign currency translation adjustment, tax (benefit)	$ (897)	$ (623)	$ 281
Derivative financial instruments adjustment, tax (benefit)	790	71	(503)
Net gains or losses and prior service costs, tax (benefit)	(4,228)	(6,417)	(319)
Amortization of prior service costs and net gains or losses, tax	$ 3,937	$ 2,359	$ 3,028
Cash dividends declared (in usd per share)	$ 6.45	$ 0.46	$ 0.44
Stock Issued Upon Exercise of Stock Options, Tax Effect	$ 0	$ 0	$ 0

Stock Issued Upon Exercise of Stock Options, Tax Effect

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- Definition

Aggregate dividends declared during the period for each share of common stock outstanding.

+ References

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-Publisher FASB
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- Definition

Amount of tax expense (benefit) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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- Definition

Amount of tax expense (benefit), before 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.

+ References

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- Definition

Amount of tax expense (benefit), after 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 of tax (expense) benefit for reclassification adjustment from accumulated other comprehensive (income) loss of defined benefit plan.

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