Savings Plans, Pension Plans and Other Postretirement Employee Benefits (Schedule of Estimated Future Benefit Payments) (Details) $ in Thousands	Dec. 31, 2019 USD ($)
Pension Plans [Member]
2020	$ 30,769
2021	30,756
2022	30,689
2023	30,589
2024	30,232
2025–2029	143,237
OPEB [Member]
2020	4,548
2021	3,780
2022	3,595
2023	3,402
2024	3,148
2025–2029	$ 12,966

Amount of benefits for defined benefit plan expected to be paid in five fiscal years after fifth fiscal year following latest fiscal year.

Reference 1: http://fasb.org/us-gaap/role/ref/legacyRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=118255775&loc=d3e1928-114920

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Amount of benefits for defined benefit plan expected to be paid in next fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fifth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in fourth fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in third fiscal year following latest fiscal year.

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Amount of benefits for defined benefit plan expected to be paid in second fiscal year following latest fiscal year.

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