CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	9 Months Ended
Sep. 30, 2019	Sep. 30, 2018	Sep. 30, 2019	Sep. 30, 2018
Statement of Stockholders' Equity [Abstract]
Tax effect of gain (losses) on derivatives qualifying as hedges	$ 348	$ 315	$ 39	$ 1,672
Tax effect of pension liability and postretirement adjustment	$ 1,937	$ 297	$ 3,038	$ 2,902
Cash dividends declared, per share	$ 0.75	$ 0.73	$ 2.21	$ 2.11

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

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-Name Accounting Standards Codification
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-SubTopic 10
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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, after reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income of defined benefit plan.

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