CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY (Parenthetical) - USD ($) $ in Thousands	3 Months Ended	6 Months Ended
Jun. 30, 2020	Jun. 30, 2019	Jun. 30, 2020	Jun. 30, 2019
Statement of Stockholders' Equity [Abstract]
Tax effect of gain (losses) on derivatives qualifying as hedges	$ 474	$ 342	$ 298	$ 387
Tax effect of pension liability and postretirement adjustment	$ (1,165)	$ (1,937)	$ (2,187)	$ (1,101)
Cash dividends declared, per share	$ 0.75	$ 0.73	$ 1.50	$ 1.46

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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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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