Accumulated Other Comprehensive Loss - Reclassifications Out of Accumulated Other Comprehensive Loss (Details) - USD ($) $ in Thousands	6 Months Ended
Jun. 30, 2018	Jun. 30, 2017
Amortization of pension and postretirement benefits items:
Prior service benefit/cost	$ (756)	$ (13)
Settlement expense	8,168
Amortization of actuarial loss	274	252
Total before tax	7,686	239
Income tax benefit	(1,914)	(85)
Amount reclassified out of accumulated other comprehensive loss	$ 5,772	$ 154

Reclassification From Accumulated Other Comprehensive Income, Current Period, Tax

No definition available.

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- Definition

Amount of payment, which decreases plan assets of defined benefit plan, for irrevocable action relieving primary responsibility for benefit obligation and eliminating risk for obligation and assets used to effect settlement. Transaction constituting settlement includes, but is not limited to, making lump-sum cash payment to participant in exchange for their rights to receive specified benefits and purchasing nonparticipating annuity contract.

+ References

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- Definition

Amount, before tax, of 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

No definition available.

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- Definition

Amount, before tax and reclassification adjustment, of (increase) decrease in accumulated other comprehensive income of defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

+ References

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- Definition

Amount, before tax, of gain (loss) for (increase) decrease in value of benefit obligation for change in actuarial assumptions and increase (decrease) in value of plan assets from experience different from that assumed of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

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- Definition

Amount after tax of reclassification adjustments of other comprehensive income (loss).

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