Retirement Benefit Plans (Schedule of Expected Benefit Payments) (Details) (USD $) In Thousands, unless otherwise specified	Dec. 31, 2014
Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2015	$ 1,526
2016	1,574
2017	1,674
2018	1,776
2019	1,818
Years 2020 through 2024	9,637
Supplemental Employee Retirement Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2015	62
2016	110
2017	149
2018	251
2019	252
Years 2020 through 2024	1,411
Hourly Employees’ Pension Plan \| Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2015	639
2016	641
2017	648
2018	656
2019	665
Years 2020 through 2024	3,269
Employees’ Retirement Plan \| Pension Plans, Defined Benefit
Defined Benefit Plan Disclosure [Line Items]
2015	887
2016	933
2017	1,026
2018	1,120
2019	1,153
Years 2020 through 2024	$ 6,368

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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=35743120&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

+ Details

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- Definition

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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- Definition

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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