CONSOLIDATED STATEMENT OF SHAREHOLDERS EQUITY (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Stockholders' Equity [Abstract]
Tax effect of gain (losses) on derivatives qualifying as hedges	$ (505)	$ 2,011	$ 2,017
Tax effect of pension liability and postretirement adjustment	$ (7,559)	$ (5,052)	$ (1,583)
Cash dividends declared, per share	$ 2.96	$ 2.84	$ 2.66

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

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 505
-SubTopic 10
-Section S99
-Paragraph 1
-Subparagraph (SX 210.3-04)
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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).

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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-Subparagraph (d)
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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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