Consolidated Statements of Comprehensive Income (Parenthetical) - USD ($) $ in Thousands	12 Months Ended
Dec. 31, 2019	Dec. 31, 2018	Dec. 31, 2017
Statement of Comprehensive Income [Abstract]
Amortization of Prior Service Credits, Tax	$ 697	$ 662	$ 1,076
Net Actuarial Loss, Tax	(3,958)	(5,590)	(9,039)
Settlement Loss, Tax	0	0	(2,312)
Other Comprehensive (Loss) Gain before Reclassification, Tax	11,690	(14,986)	(26,360)
Unrealized Loss on Cash Flow Hedges, Tax	$ (37)	$ 0	$ 0

Other Comprehensive Income (Loss), Defined Benefit Plan, Actuarial Gain (Loss) Arising During Period, Tax

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- Definition

Other Comprehensive Income (Loss), Defined Benefit Plan, Adjustment for Settlement Gain (Loss), Tax

+ References

No definition available.

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- Definition

Amount of tax expense (benefit) for reclassification of gain (loss) from accumulated other comprehensive income (AOCI) for derivative instrument designated and qualifying as cash flow hedge included in assessment of hedge effectiveness.

+ References

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-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
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- Definition

Amount, before reclassification adjustment, of tax (expense) benefit for (increase) decrease in accumulated other comprehensive income for defined benefit plan.

+ References

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- Definition

Amount of tax (expense) benefit for cost (credit) of benefit change attributable to participants' prior service from plan amendment or plan initiation of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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- References

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