Pension and Other Benefits (Details) - Schedule of Allocation of Plan Assets	12 Months Ended
Dec. 31, 2017	Dec. 31, 2016
Equity Securities
% of Plan Assets	100.00%	100.00%
Weighted Average Expected Long-Term Rate of Return	5.50%	5.50%
Domestic Equity Securities [Member]
Equity Securities
Target Allocation	42.00%	42.00%
% of Plan Assets	41.00%	44.00%
Weighted Average Expected Long-Term Rate of Return	3.20%	3.20%
International Equity Securities [Member]
Equity Securities
Target Allocation	10.00%	10.00%
% of Plan Assets	8.00%	8.00%
Weighted Average Expected Long-Term Rate of Return	0.70%	0.70%
Debt And Fixed Income Securities [Member]
Equity Securities
Target Allocation	46.00%	46.00%
% of Plan Assets	49.00%	47.00%
Weighted Average Expected Long-Term Rate of Return	1.60%	1.60%
Cash And Other Alternative Investments [Member]
Equity Securities
Target Allocation	2.00%	2.00%
% of Plan Assets	2.00%	1.00%
Weighted Average Expected Long-Term Rate of Return	0.00%	0.00%

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- Definition

Weighted average rate of return on plan assets, reflecting average rate of earnings expected on existing plan assets and expected contributions, used to determine net periodic benefit cost of defined benefit plan.

+ 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 (k)(3)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of target investment allocation to total plan assets. Includes, but is not limited to, percentage on weighted-average basis if more than one plan.

+ 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 (d)(5)(i)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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- Definition

Percentage of fair value of investments (categorized by debt securities, equity securities, real estate and other plan assets) to the fair value of plan assets held.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2446-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 1
-Subparagraph (d)(1)
-URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e1928-114920

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