Postretirement Benefits (Details 11) $ in Thousands	Dec. 31, 2017 USD ($)
Benefits expected to be paid over the next 10 years from pension plans:
2018	$ 20,739
2019	23,050
2020	25,665
2021	28,687
2022	31,650
2023-2027	$ 210,951

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

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (f)
-URI http://asc.fasb.org/extlink&oid=82843861&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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