Consolidated Statements Of Shareholders' Equity (Parenthetical) - USD ($)	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Stockholders' Equity [Abstract]
Foreign currency translation adjustment, tax (benefit)	$ 177,000	$ 0	$ 1,106,000	$ 0
Derivative financial instruments adjustment, tax (benefit)	339,000	(134,000)	887,000	(51,000)
Amortization of prior service costs and net gains or losses, tax	$ 835,000	$ 593,000	$ 1,671,000	$ 1,185,000
Cash dividends declared, per share	$ 0.12	$ 0.11	$ 0.24	$ 0.22

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

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

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