Retirement Plans (Schedule of Expected Benefit Payments) (Details) $ in Thousands	Dec. 31, 2016 USD ($)
Pensions [Member]
Expected Future Benefit Payments [Abstract]
2017	$ 18,453
2018	18,743
2019	19,078
2020	19,365
2021	19,650
2022 through 2026	101,161
Supplemental Employee Retirement Plans [Member]
Expected Future Benefit Payments [Abstract]
2017	2,076
2018	1,897
2019	1,817
2020	1,733
2021	1,646
2022 through 2026	6,721
Other Postretirement Benefit Plans [Member]
Expected Future Benefit Payments [Abstract]
2017	150
2018	145
2019	139
2020	133
2021	127
2022 through 2026	$ 540

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the five fiscal years after the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ 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=58740216&loc=d3e1928-114920

+ Details

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- Definition

Amount of benefits from a defined benefit plan expected to be paid in the next fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the fifth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the fourth fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the third fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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Amount of benefits from a defined benefit plan expected to be paid in the second fiscal year following the latest fiscal year. Excludes interim and annual periods when interim periods are reported on a rolling approach, from latest balance sheet date.

+ References

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