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Employee Benefits - Cash Flows Narrative (Details) - Pension Plan $ in Millions | Dec. 31, 2017 USD ($)
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U.S. |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Expected employer contributions during next fiscal year | $ 92
U.K. |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Expected employer contributions during next fiscal year | 63
Other |
Defined Benefit Plans and Other Postretirement Benefit Plans Table Text Block [Line Items] |
Expected employer contributions during next fiscal year | $ 22

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- Definition Amount of contributions expected to be received by defined benefit plan from employer in next fiscal year following latest fiscal year. + 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=82843861&loc=d3e1928-114920 + Details
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