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Accounting Policies (Tables) | 12 Months Ended
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Dec. 31, 2017
Accounting Policies [Abstract] |
Schedule of Range of Estimated Service Lives | The range of estimated service lives used to calculate financial reporting depreciation for principal items of plant and equipment are as follows:
Buildings | 15 – 45 Years
Machinery and equipment | 5 – 40 Years
Other | 3 – 25 Years

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