Savings Plans, Pension Plans and Other Postretirement Employee Benefits (Amounts Recognized in AOCI on Consolidated Balance Sheet) (Details) - USD ($) $ in Thousands	Dec. 31, 2018	Dec. 31, 2017
Pension Plans [Member]
Net loss	$ 128,849	$ 100,070
Prior service cost (credit)	404	541
Net amount recognized	129,253	100,611
OPEB [Member]
Net loss	7,269	10,165
Prior service cost (credit)	(8,651)	(15,220)
Net amount recognized	$ (1,382)	$ (5,055)

Amount, after tax, of accumulated other comprehensive (income) loss for defined benefit plan, that has not been recognized in net periodic benefit cost (credit).

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 220
-SubTopic 10
-Section 45
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- Definition

Amount, after tax, of accumulated other comprehensive income (loss) for gain (loss) of defined benefit plan, that has not been recognized in net periodic benefit (cost) credit.

+ References

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Amount, after tax, of accumulated other comprehensive (income) loss 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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