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Employee Benefit Plans (Target Allocation, Percentage Of Plan Assets And Weighted Average Expected Rate Of Return) (Details)	12 Months Ended
	Dec. 31, 2016	Dec. 31, 2015
Cash And Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	20.00%
Percentage of Plan Assets	6.10%	5.20%
Weighted Average Expected Long-term Rate of Return	0.18%
Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	40.00%
Target Allocation, Maximum	60.00%
Percentage of Plan Assets	47.90%	47.20%
Weighted Average Expected Long-term Rate of Return	3.89%
Fixed Income Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	40.00%
Target Allocation, Maximum	60.00%
Percentage of Plan Assets	42.60%	43.90%
Weighted Average Expected Long-term Rate of Return	2.14%
Other Financial Instruments [Member]
Defined Benefit Plan Disclosure [Line Items]
Target Allocation, Minimum	0.00%
Target Allocation, Maximum	5.00%
Percentage of Plan Assets	3.40%	3.70%
Weighted Average Expected Long-term Rate of Return	0.26%

X

- Definition

Defined Benefit Plan, Weighted Average Expected Long-Term Rate Of Return

+ References

No definition available.

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+ References

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- Definition

Target allocation maximum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

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Target allocation minimum percentage of investments of this type to total plan assets presented on a weighted average basis.

+ 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)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e1928-114920

Reference 2: http://www.xbrl.org/2003/role/presentationRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 715
-SubTopic 20
-Section 50
-Paragraph 5
-Subparagraph (c)(i)
-URI http://asc.fasb.org/extlink&oid=58740216&loc=d3e2446-114920

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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=58740216&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=58740216&loc=d3e1928-114920

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