v3.8.0.1

Employee Benefit Plans (Information for Pension Plans with a Projected and Accumulated Benefit Obligation in Excess of Plan Assets) (Details) - USD ($) $ in Millions | Dec. 31, 2017 | Dec. 31, 2016
--- | --- | ---
Defined Benefit Plan, Plan with Benefit Obligation in Excess of Plan Assets [Abstract] |  |
Projected benefit obligation | $ 2,875 | $ 2,638
Fair value of plan assets | 47 | 44
Information On Pension Plans With Accumulated Benefit Obligation In Excess Of Plan Assets [Abstract] |  |
Accumulated benefit obligation | 2,655 | 2,426
Fair value of plan assets | $ 0 | $ 4

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- Definition Amount of accumulated benefit obligation for defined benefit pension plan with accumulated benefit obligation in excess of plan assets. + References Reference 1: http://www.xbrl.org/2003/role/presentationRef -Publisher FASB -Name Accounting Standards Codification -Topic 715 -SubTopic 20 -Section 50 -Paragraph 3 -Subparagraph (b) -URI http://asc.fasb.org/extlink&oid=82843861&loc=d3e2417-114920 + Details
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