The difference between fair value of plan assets at the end of the period and the fair value at the beginning of the period, adjusted for contributions and payments of benefits during the period, and after adjusting for taxes and other expenses, as applicable, measured as a percentage.

No definition available.

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- Definition

An assumption as to the rate of return on plan assets reflecting the average rate of earnings expected on the funds invested or to be invested to provide for the benefits included in the benefit obligation.

+ References

Reference 1: http://www.xbrl.org/2003/role/presentationRef

-Publisher FASB

-Name Accounting Standards Codification

-Topic 715

-SubTopic 30

-Glossary Expected Long-Term Rate of Return on Plan Assets

-URI http://asc.fasb.org/extlink&oid=6512013

Reference 2: 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=35743120&loc=d3e1928-114920

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- Definition

Amount of employer's best estimate of contributions expected to be paid to the plan during the next fiscal year beginning after the date of the latest statement of financial position.

+ 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 (g)

-URI http://asc.fasb.org/extlink&oid=35743120&loc=d3e1928-114920

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Benefit Obligations (Plan Assets Narrative) (Details) (USD $) In Millions, unless otherwise specified	12 Months Ended
	Dec. 31, 2014	Dec. 31, 2013	Dec. 31, 2012	Dec. 31, 2015
Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets	8.20%	8.00%	8.10%
Estimated employer contributions for pension benefits and postretirement benefits	$ 60
United States Pension Plan of US Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Actual return on plan assets	13.70%
Expected return on plan assets	8.50%	8.50%	8.50%
Postretirement Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated employer contributions for pension benefits and postretirement benefits	5
Nonqualified Pension Benefits [Member]
Defined Benefit Plan Disclosure [Line Items]
Estimated employer contributions for pension benefits and postretirement benefits	$ 22
Scenario, Forecast [Member] \| United States Pension Plan of US Entity [Member]
Defined Benefit Plan Disclosure [Line Items]
Expected return on plan assets				8.00%