Retirement And Employee Benefit Plans (Schedule Of Allocation Of Plan Assets) (Details) - Pension Benefits [Member]	12 Months Ended
Dec. 31, 2015
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	100.00%
Actual asset allocations	100.00%
Fixed Income [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	28.00%
Actual asset allocations	28.00%
Cash and Cash Equivalents [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	2.00%
Actual asset allocations	2.00%
U.S. Equity [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	35.00%
Actual asset allocations	36.00%
Non-U.S. Developed Equity [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	30.00%
Actual asset allocations	29.00%
Emerging Market Equity [Member] \| Equity Securities [Member]
Defined Benefit Plan Disclosure [Line Items]
Target asset allocations	5.00%
Actual asset allocations	5.00%

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- Definition

Target allocation 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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- 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=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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